IQP – 43 - DSA - 3001 IQP – 43 - DSA - 1845 IQP – 43 - DSA - 6882 IQP – 43 - DSA - 0994
TRANSGENIC ANIMALS
An Interactive Qualifying Project Report
Submitted to the Faculty of
WORCESTER POLYTECHNIC INSTITUTE
In partial fulfillment of the requirement for the
Degree of Bachelor of Science
By:
______Marcella Corcoran Nicholas Maloney Whitney Moore Sara Munro
August 25, 2004
APPROVED:
______Prof. David S. Adams, Ph.D. Project Advisor
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ABSTRACT
Transgenic animals are animals that have been genetically altered by inserting a transgene into their genomes to express a new trait. This IQP provides an overview of the construction of transgenic animals, the categories they fall into, and notable examples of each type. The effects of this new technology on both science and society were investigated by describing current ethical and legal debates. Finally, conclusions were formulated based on our research.
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TABLE OF CONTENTS
Page Signature Page…………………………………………………………………………………..1
Abstract………………………………………………………………………………………… 2
Table of Contents………………………………………………………………………………..3
Executive Summary……………………………………………………………………………..4
Project Objective………………………………………………………………………………...7
Chapter 1: Transgenic Animal Description and Construction…………………………………..8
Chapter 2: Transgenic Animal Classification and Examples…………………………………..18
Chapter 3: Transgenic Ethics…………………………………………………………………...37
Chapter 4: Transgenic Legalities……………………………………………………………….57
Chapter 5: Conclusions…………………………………………………………………………67
Bibliography……………………………………………………………………………………70
3 EXECUTIVE SUMMARY
Transgenic animals are animals that have had their DNA genetically transformed to
express or mimic a useful feature that is not normally expressed in that species. Scientists have a
wide variety of reasons for wanting to create genetically altered animals that not only affect science but also society. There are five main categories of transgenic animals. The first category, disease models, includes animals such as Alzheimer’s mouse, AIDS Mouse, and
OncoMouse™ that are engineered to mimic some aspect of a human disease. These animals provide models for investigating disease mechanisms and potential cures. The second category, transpharmers, includes animals engineered to express protein drugs or antibiotics in their milk.
These animals provide a convenient source for new medications with no animal sacrifice. This category includes such models as Baby Herman (the world’s first transgenic cow, whose female offspring provide the first successful bovine transpharmer) and the Genzyme goats. These animals provide new sources for drugs we normally synthetically produce. The third category is the xenotransplanters that are engineered to produce organs compatible with humans. The fourth
category is transgenic food sources, that include animals like Superpig and Superfish that are
engineered to be larger than normal. The last group of transgenics include the scientific models
that teach us something new about a specific protein’s function in vivo. Each group contains
animals that have brought both positives as well as negatives to science and society.
The main question surrounding transgenic animals is that now that we have the
knowledge and technology to create these animals, should we? As is typical of any new
powerful technology, its affects on society are far reaching. The creation of transgenic animals
raises many ethical debates. While some see the technology negatively as tampering with life
and trying to play God, others are very optimistic and see these animals as extremely beneficial
4 to human life. Many religions and animal rights activists frown upon genetically altering an
animal, even in those cases where it is for the good of the human race. These groups show
concerns with the creation, maintenance, usage, and suffering of these animals. For example,
with the OncoMouse™, the mouse is induced with cancer, but its suffering provided huge
advancements for the treatment and diagnosis of cancer in humans. On the other hand, in the
case of the Superpig, the animal suffered greatly and was sacrificed; its original purpose was for
healthier meat. Ethically, these two animals pose different views even though each animal has a
transgenic alteration and both animals suffered. The OncoMouse™ suffered for a good cause and
advanced the medical community, and the Superpig suffered as an unsuccessful food source,
making the OncoMouse™ a more positive experiment. These two examples demonstrate why
ethics must be determined by keeping the purpose and success in mind. Following the research
performed for this IQP, we authors feel that each transgenic category serves a unique purpose,
and therefore the ethics surrounding these animals must be considered on a case by case basis.
We believe that in those specific cases where there is strong documented medical benefit, with
little or no animal suffering, transgenic technology should be supported, but not in those cases
with no clearly documented medical benefit.
Transgenic technology also has legal ramifications. Harvard and Dupont’s OncoMouse™
is the world’s first patented animal, having received patents in the U.S. and several European countries. However, not all countries agree that animals can be patented; the OncoMouse™
patent case has recently been rejected in Canada. Although the Canadian case involved many
appeals, it was eventually the decision of the courts that the oncomouse is not an invention, but
an unpatentable higher life form. In the U.S., the case raised so many key issues that
amendments were issued to the U.S. law to oversee and govern the creation, usage, and treatment
5 of transgenic animals. Presently, the United States patent laws allow the patenting of animals as long as the new creation remains “non-obvious” compared with former creations. “A definition of what is non-obvious in the eyes of the court has been explained to include something that a hypothetical worker of the relevant field, devoid whatsoever of any imagination and inventive capacity, though infinitely knowledgeable of and versed in the prior art and the common knowledge of the relevant field, could never have produced” (James, 2001).
The writers of this IQP deem many of the categories these animals fall under as acceptable and beneficial to humans. However, it is important to set rules and regulations to ensure that these animals are created using proper techniques and to ensure that they do not suffer in any way. It is our opinion that transgenic animals will have a bright future in science as well as society.
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PROJECT OBJECTIVE
The objective of this project was to explore the new technology of transgenic animals, and investigate its effects on science and society. In order to reach this goal, we first needed to form a strong background on the topic. So we began by researching what a transgenic animal was and how they were created. After building a solid foundation of understanding, we studied the different categories of transgenic animals as well as the contributions and uses of each. In turn, our investigation moved towards the many ethical and legal debates that surround these animals. This project allowed us to understand how scientific breakthroughs can affect much in our daily lives and have so many different views.
7 CHAPTER 1: WHAT IS A TRANSGENIC ANIMAL?
Nicholas Maloney and Sara Munro
The term transgenic animal refers to an animal in which there has been a deliberate
modification of the genome, usually to insert a foreign gene. In biology, the genome of an
organism represents an entire set of chromosomes; for example, one of the two sets that a diploid
individual carries in every somatic cell. Foreign DNA is introduced into the animal, using
recombinant DNA technology, and then must be transmitted through the germ line so that every cell, including germ cells, of the adult animal contain the same modified genetic material.
Recombinant DNA technology is a body of techniques for cutting apart and splicing together different pieces of DNA. When segments of foreign DNA are transferred into another cell or organism, the protein that gene encodes may be produced along with substances encoded by the native genetic material of the cell or organism. Thus, these animals become "factories" for the production of the protein encoded by the inserted DNA.
Transgenic History
Before the development of molecular genetics, the only way of studying the regulation and function of mammalian genes was through the observation of inherited characteristics or spontaneous mutations. Long before Mendel and any molecular genetic knowledge, selective breeding was a common practice among farmers for the enhancement of chosen traits, i.e.,
increased milk production.
The first chimeric mice were produced during the 1970s (Brinster, 1990). A chimera is
an organism that contains a mixture of genetically different cells (i.e. some transgenic, some
8 not). The cells of two different embryos of different strains of mice were combined together at an early stage of development (the eight cell stage) to form a single embryo that later developed into a chimeric adult. The adult was chimeric because it exhibited characteristics of each strain of the two original embryos.
The combined contributions of developmental biology and genetic engineering permitted a quick development of the techniques used for the creation of transgenic animals. DNA microinjection was the first transgenic technique to prove successful in mammals. It was first applied to mice (Wortman, 2000) and then to various other species such as rats, rabbits, sheep, goats, cows, pigs, birds, chickens, and even fish. Two other techniques that were later developed were called retrovirus-mediated transgenesis and embryonic stem (ES) cell-mediated gene transfer.
The term “transgenic” was first used by J.W. Gordon and F.H. Ruddle in 1981 (Rülicke,
2004). In 1980, Gordon and Ruddle produced the first transgenic mouse through pronuclear- injection of a fertilized egg cell (Maher, 2002). Since then, there has been rapid development in the use of genetically engineered animals as investigators have found an increasing number of applications for the technology. Some examples of transgenic uses are in the pharmaceutical, therapeutic, agricultural, and medical industries. These examples will be discussed further in chapter 2.
9 Transgenic Methodology
As stated earlier, there are various ways of creating a transgenic animal. Today the
principal methods used are: DNA microinjection into the oocyte pronucleus, DNA homologous
recombination with ES cells, DNA viral delivery into ES cells, and DNA chemical delivery into
ES cells.
DNA Microinjection into Oocyte Pronucleus
The first method, DNA microinjection, involves the direct microinjection (Figure1) of a
chosen gene construct (a single gene or a combination of genes) from another member of the
same species or from a different species, into the pronucleus of a fertilized ovum. A pronucleus is the nucleus of the ovum (female) or sperm (male) after fertilization but before they fuse together to form the nucleus of the zygote. This method is one of the first methods that proved to be effective in mammals.
Figure 1: Injection of Cloned DNA Into Embryos. A one-cell embryo is positioned for micro-injection into the pronucleus using a mild suction pipette to hold the cell in place (left part of diagram). The plasma membrane is pierced (right side of the diagram), and the tip of the needle remains inside the pronucleus, while DNA is expelled from the needle (center of the diagram), causing the pronucleus to swell visibly (Gardner, 1965).
The introduced “foreign” DNA may lead to the over- or under-expression of certain
genes, or to the expression of genes entirely new to the animal’s species. The integration of the
transgene into the host nucleus is a random process, and there is no way of controlling where it
integrates in the host’s genome. In some cases, the transgene inserts into an inactive region of a
chromosome, and never becomes expressed. Because the integration is a random process, there
10 is a high probability that the introduced gene will not insert itself into a site on the host DNA that
will permit its expression. The manipulated fertilized ovum is transferred into the oviduct of a recipient female, or foster mother that has been induced to act as a recipient by mating with a vasectomized male. A vasectomized male has had all or part of his vas deferens removed as a means of sterilization. The major advantage to this method is its applicability to a wide variety of species, and it still remains one of the most commonly used methods for creating transgenic animals.
Brief Introduction to Stem Cells
Because several methods for creating transgenic animals use stem cells, and there are several types, it is worth our time to briefly discuss them. Stem cells are cells that display two main properties: when they divide by mitosis the daughter cells can either enter a path leading to a fully-differentiated cell, or it can remain a stem cell thus ensuring that the pool of stem cells is not “used up”. Several adjectives are used to describe the developmental potential of stem cells
(the number of different kinds of differentiated cell that they can become). The first kind of stem
cell is called a totipotent cell. In mammals, totipotent cells have the potential to become any
type in the adult body and any cell of the extraembryonic membrane. The only totipotent cells
are the fertilized egg and approximately the first four cells produced by its cleavage (as shown by
the ability of mammals to produce identical twins, triplets, etc).
Another kind of stem cell is called “pluripotent”. Pluripotent stem cells are true stem
cells, with the potential to make any differentiated cell in the body, but cannot contribute to
making the extraembryonic membranes. Three types of pluripotent stem cells have been found.
11 The first type is embryonic (ES) stem cells. These can be isolated from the inner cell mass
(ICM) of a blastocyst (the stage of embryonic development when implantation occurs (Figure 2).
Figure 2: Diagram of a Typical Mammalian Blastocyst. At the blastocyst stage, the embryo consists of a hollow ball of cells. The outer layer (pink in the diagram) is the trophoblast, and the inner layer (green in the diagram) is the inner cell mass. The latter contains the ES cells manipulated while making a transgenic animal
Because embryos can easily be obtained by in vitro fertilization, ES cells are frequently used to create transgenic animals. Figure 3 shows a micrograph of several ES cells.
Figure 3: A microscopic view of human embryonic stem cells (Touchette, 2003).
The second type of pluripotent cell is the embryonic (EG) germ cell. These can be isolated from the precursor to the gonads in aborted fetuses. Because of their isolation from fetuses, such cells are rarely used nowadays. The third type of pluripotent stem cells is the embryonic (EC) carcinoma cell. These cells can be isolated from teratocarcinomas, tumors that
12 occasionally occur in a gonad of a fetus. Unlike the other two, they are usually aneuploid
(chromosomes that have extra or fewer than the normal diploid chromosomes). As with EG cells, because EC cells can only be isolated from fetuses, they are used less frequently than ES cells. All three of these types of pluripotent stem cells can be grown in culture, but only by special methods to prevent them from differentiating.
The final type of stem cell is called “multipotent”. Multipotent stem cells are true stem cells but can only differentiate into a limited number of cell types. For example, the bone marrow contains hematopoietic stem cells (HSCs) that give rise to all the cells of the blood, but not to other types of cells. Multipotent stem cells are found in adult animals; perhaps every organ in the body contains them so they can replace dead or damaged cells.
DNA Microinjection into ES Cells
The second method for preparing transgenic animals uses microinjection into ES cells. The process of microinjecting ES cells is a complex one because the isolation of the ES cells to be manipulated is more difficult than obtaining a fertilized egg by in vitro fertilization. The ES cells are usually prepared by the following steps: an egg is fertilized by in vitro fertilization, then cultured to the blastocyst stage. At that stage, the ES cells are present in the inner cell mass
(Figure 2). ES cells for injection should be in the log phase of growth. They should be thawed and passed for one generation prior to microinjection. On the day of injection, the investigator trypsinizes the ES cells to separate them prior to injection.
The purification of a DNA fragment for microinjection is extremely important to rid contaminating salts, organic solvents, or traces of agarose, is in the correct and sterile buffer and, is not sheared or nicked. Usually the transgene is cloned into a plasmid (as a vehicle), and
13 purified by cesium chloride density centrifugation or a Qiagen column. The fragment of interest
is then isolated from vector sequences by restriction enzyme digestion and electrophoresis, removing as much of the vector sequences as possible. Once the ES cells and the DNA have both been prepared, the investigator can then microinject the DNA into the ES cells. The DNA-
injected ES cells are then cultured to the blastocyst stage, then implanted into a surrogate mother.
DNA Homologous Recombination with ES Cells
The third method of creating a transgenic animal is done by DNA homologous recombination with ES cells. This method involves prior insertion of the desired DNA sequence by homologous recombination into an in vitro culture of embryonic stem (ES) cells. An “in vitro” (Latin for “in glass”) culture is one that is done outside of a living organism, most commonly in a test tube. Contrary to an in vitro culture is an “in vivo” culture that is done inside a living organism. Homologous recombination occurs between two homologous or similar
DNA molecules. It is also called DNA crossover. During meiosis, two homologous pairs of sister chromatids align side by side. The DNA crossover can occur as often as several times per meiosis, with similar portions of a pair of chromatids exchanging places.
By injecting a transgene coupled to chromosomal DNA into an ES cell, the plasmid chromosomal DNA exchanges places with its corresponding “sister” region in the ES chromatid, bringing the transgene with it as it recombines. This process incorporates the transgene into the
ES cell. These cultured ES cells are then microinjected into a donor embryo at the blastocyst stage of development. If successful, the result is a chimeric animal. ES cell-mediated gene transfer is the method of choice for gene inactivation, the so-called knock-out method. It is called this because the gene transfer shuts off or “knocks out” the process of another gene. This
14 technique is of particular importance for the study of the genetic control of developmental processes since it can remove expression of a specific protein allowing the effects of its absence to be determined on the animal. This technique works particularly well in mice. Some examples of mice that were used in this manner are the p53 (a gene thought to play a key role in tumor suppression) knockout mice and the cystic fibrosis mice (Strategis, 2004). It has the advantage of allowing the precise targeting of defined mutations in a gene via homologous recombination.
Figure 4: Diagram displays Methods 1 and 2 of the Embryonic Stem Cell Method for Making a Transgenic Animal (Transgenic Animals, 2003).
15 DNA Viral Delivery into ES Cells
The fourth method of creating a transgenic animal is retrovirus-mediated gene transfer.
To increase the probability of expression, transgene transfer is mediated by means of a carrier or
vector, generally a virus or a plasmid. A retrovirus is any virus in the family Retroviridae that
has RNA as its nucleic acid and uses the enzyme reverse transcriptase to copy its genome into
the DNA of the host cell's chromosomes. Many cancers in vertebrates are caused by retroviruses.
A retrovirus’ genome that is integrated into the host’s genome is called a provirus. Retroviruses are commonly used as vectors to transfer genetic material into the cell because of their ability to infect host cells in this way. Offspring derived from this method are chimeric, i.e., not all cells
carry the retrovirus. Transmission of the transgene to offspring is possible only if the retrovirus
integrates into some of the germ cells.
For any of these techniques the success rate in terms of live birth of animals containing
the transgene is extremely low, especially for large animals. Providing that the genetic
manipulation does not lead to abortion, the result is a first generation (F1) of animals that need to
be tested for the expression of the transgene. Depending on the technique used, the F1 generation
may result in chimeras. When the transgene has integrated into the germ cells, the so-called germ
line chimeras are then inbred for 10 to 20 generations until homozygous transgenic animals
(those containing only copies of the transgene at a given site, and not the non-transgenic sister
allele) are obtained and the transgene is present in every cell. At this stage of the experimental
process, embryos carrying the transgene can be frozen and stored for subsequent implantation. A
scientist would freeze the embryos in order to preserve them without damaging them.
16 DNA Chemical Delivery into ES Cells
The final method of creating a transgenic animal is very similar to the previous method of
DNA viral delivery but in this method, however, the carrier or vector is a chemical opposed to a retrovirus.
After describing the main ways to make a transgenic animal, we now focus our attention on their classification in the next chapter.
17 CHAPTER 2: TRANSGENIC ANIMAL CLASSIFICATION AND EXAMPLES
Marcella Corcoran and Whitney Moore
Having discussed the inner workings of transgenic animals in chapter one will now allow us to categorize them efficiently in this chapter. Most scientists will agree that mice have been the pioneers in the study and creation of transgenic animals. Mice are very popular transgenic animals because extensive studies have been done on their genome and they are relatively inexpensive and easy to maintain compared to other mammals, thus much has been discovered using them as model systems. Mice aren’t the only animals being genetically altered. Many other animals including pigs, sheep, goats, fish, flies, and even a monkey have been transformed into transgenic animals. Transgenic animals are created for many purposes and in many cases they have been useful, both in a positive light as well as in the negative, to science and society.
There are five basic categories that these animals fall under, which include disease models, transpharmers, xenotransplanters, food sources, and biological (scientific) models. The purpose of this chapter is to describe, categorize, and discuss many well known examples of transgenic animals. Each category contains the most popular transgenic animals and other notable examples that will prove useful in subsequent chapters on transgenic ethics and legalities.
Disease Models
Many diseases including polio and small pox previously took the lives of millions of
innocent people, but fortunately vaccines are now available for those specific diseases. Although
18 these medical breakthroughs have been successful in saving many lives, some deadly diseases
still do not have a cure. Transgenic disease models are created to mimic human diseases so
scientists can learn more about the diseases including symptoms, pathways, causes, and research
treatments, as well as possible cures. Animal models are cheaper and contribute less ethical
consequences than vaccine and drug testing in humans. Just as was the case with polio and
smallpox where animal studies led to successful vaccines, as scientists continue their research on other diseases, successful treatments with animals could hopefully someday be approved for human clinical trials.
In this category the most well-known examples are Alzheimer’s Mouse, OncoMouse™,
AIDS Mouse, ANDi, and Super Fly. These engineered animals allow scientists to better understand how various genes contribute to the development of diseases. Each of these animals is essential for leading to successful human trials. By studying these animals, scientists can hopefully find the key to unlock the cures to painful diseases, and give those that suffer a second chance at life.
Alzheimer’s Mouse
Alzheimer’s Mouse was created in 1995 by Professor David Adams and his colleagues at
Athena Neurosciences Incorporated, formally known as Exemplar Corporation or TSI
Corporation (Games et al, 1995). In this study, Alzheimer’s disease was artificially created in mice who do not normally acquire the disease. The goal of this study was to move one step closer to creating a vaccine for the disease (Adams, 2003) that affects approximately 4.5 million
Americans (Alzheimer’s Association, 2004).
19 In the study, mice were engineered to produce a mutated form of human amyloid. The
transgene used to create Alzheimer’s symptoms encodes human amyloid with a mutation to
resemble an Indiana family, FAD, with early onset disease (average age of onset is 40 years
versus 70 years for sporadic Alzheimer’s disease) (Games et al, 1995; Adams, 2003). As a result
of this study it was discovered that amyloid plays a huge role in causing the disease (Adams,
2003).
Amyloid normally functions as a transmembrane protein, and is degraded by normal
enzymes to generate low molecular weight products. In Alzheimer’s disease, normal amyloid
degradation switches to produce highly toxic degradation products that cause neurodegeneration.
So this disease is an amyloid protein processing disease. The toxic byproducts also create senile
plaques that are a hallmark feature of this disorder. The mutated version of the amyloid gene
found in a variety of early onset Alzheimer’s families causes the amyloid plaques to form faster
than usual, so Adams and colleagues used this mutated version to generate plaques faster in the
mice (Adams, 2004).
The debate was whether the senile plaques cause the disease, or are merely a result or side-product of the disease. Alzheimer’s Mouse showed that adding the mutant human amyloid gene to mice altered amyloid processing, resulting in neurodegeneration parallel to that of the
Alzheimer’s disease attacking the human brain. Adams and colleagues also discovered that the greatest number of senile plaques does not also mean the worst dementia (Adams, 2003), so perhaps it is the amyloid precursors to plaque formation (processed amyloid protein) that actually cause the disease. As a result of this study, it was proven that amyloid formation is a key cause of the disease, and that the human FAD amyloid gene is, as Professor David Adams is
quoted saying, “necessary and sufficient for initiating Alzheimer’s” (Adams, 2003). Also, when
20 the plaques (and their toxic precursors) were removed, the animals become healthier (Schenk et
al, 1999). The study of this mouse is without a doubt necessary as the first step in the development of a vaccine for Alzheimer’s disease (Schenk et al, 1999; Adams, 2004).
The model engineered by Adams and colleagues was successful because this group was the first to test FAD. They also used the PDGF promoter, which directly targeted amyloid expression to the same areas of the brain affected in Alzheimer’s patients, and they also left in some introns, which allowed the creation of all three known isoforms of amyloid protein
(Adams, 2003). In 1999 Elan Pharmaceuticals (formerly Athena Neurosciences) developed the first vaccine for Alzheimer’s disease, which is currently in phase-II human trials (Schenk et al,
1999).
OncoMouse™
Cancer is a very painful disease, not only for infected patients but also for families, friends, and loved ones. A person with cancer has cells that no longer respond to signals that limit their ability to divide and multiply. In a sense, their cells are “out of control”.
This well-known example of a transgenic disease model was created at Harvard Medical
School, patented by Dr. Philip Leder, and later licensed to DuPont Pharmaceuticals (Thompson,
2002). Dr. Leder and colleagues used the technique of inserting active oncogenes into special strains of laboratory mice. These transgenic mice carry these cancer-causing genes, pass them onto their offspring, and in turn, their offspring are very likely to develop cancer (Thompson,
2002). These mice are useful models for studying human cancers such as breast and blood cancers (also known as leukemias and lymphomas) because those are the types of cancers that the mice in this study develop (Leder, 2003).
21 The transgenic oncomice showed scientists that some human cancers are the result of two
or more oncogenes working together. One transgenic mouse line that Leder and his colleagues
have created contain a gene for one of the fibroblast growth factors, which is a gene that codes
for a biological growth-inducing factor that can be seen in many cases of human breast cancer.
The gene expressed in breast tissue induces the
proliferation of mammary epithelial cells, and an
unregulated expression of this gene, fgf7, causes breast
cancer in mice. Tumors arise when the mice are Figure 5: Above is Philip Leder's OncoMouse™ with a tumor directly behind its right front leg about one year old, which is about the same as a (Leder, 2003).
middle-aged human female. The gene fgf7 however, is found in all mammary cells during the
early life of the mouse and therefore it is not the only factor contributing to the formation of the
breast tumors. The next task at hand was for Leder and company to figure out what other genes
are contributing factors to the tumors (Leder, 2003). These scientists used a virus known to infect and integrate itself within or among mammary cells also known as a MMTV (mouse mammary tumor epithelial virus). The MMTV is considered an insertional mutagen. If the mutation the virus causes serves as an oncogene that can work with the initiation oncogene (in this case is fgf7), the mammary cell that received the viral insertion will proliferate and become a malignant tumor. Throughout this study, it was discovered that transgenic mice that were infected with
MMTV developed tumors more rapidly than normal transgenic mice. Leder and his colleagues also have the genetic tools that allow them to find the region of the mouse genome that the
MMTV was inserted into, and in turn they can figure out nearby genes that must be one of the collaborating genes of the transgenic oncongene (Leder, 2003).
22 Research has shown that collaborating genes do not occur randomly, and they are usually members of the Wnt family of genes, which are genes that play a key role in proliferation, differentiation, and the development in a number of embryonic organs. The Wnt family, along with the misexpression of fgf7 can cause cancer. Wnt10b, a member of the Wnt family, has been shown to have the ability to induce breast cancer (Leder, 2003).
Similar studies have been conducted on another initiating oncogene, Her2, and although studies must be continued, scientists have also been able to create a very good transgenic mouse using its rat homolog, neu. Researchers hope that as they continue to uncover the contributing partners of the transgenic oncogene it will allow them to someday find a cure that can be used for human cancers. OncoMouse™ is considered the “gray area” in the ethical study of disease models in that it has medical benefits and is cost effective (Thompson, 2002), but the animal does suffer as the cancer progresses (Leder, 2003).
AIDS Mouse: HIV Rodent
The Human Immunodeficiency Virus (HIV) was first discovered in humans in 1983
(Barre-Sinoussi et al) and since then, more money has been spent trying to find its cure than on any other viral disease. This virus attacks cells in the immune system and eventually results in an immuno-shutdown, a hallmark of full-blown AIDS. HIV is a virus that contains its own genetic code. In order to infect a human cell, the virus’ RNA genetic code enters the human cell and the virus copies its own genetic code into DNA. Then viral DNA copies are inserted into the DNA of the host cell. The viral DNA becomes part of the human DNA and can continuously copy itself over and over when the human cell normally divides. Each integrated viral copy can then
23 genetically express itself to make new viral copies (Bunce, 1998-2004). Since the virus mutates
rapidly, a vaccine or cure has been very hard to discover.
Various transgenic mice containing a variety of HIV genes have been used in numerous
AIDS studies, and as a result they have developed skin lesions, hyperplasia, lymphoma, loss of white blood cells, and mild immunodeficiency. However mice do not embody all the areas of the disease linked with humans (Kohn, 2001). In 2001, the first HIV rodent model was created to further the diagnostic study of the virus (Reid et al, 2001). Reid and colleagues created a transgenic AIDS rodent that, at five to nine months of age, showed many symptoms of AIDS including cataracts, weight loss, muscle atrophy, neurological abnormalities, and breathing problems. Also, the transgene can be seen in the lymph nodes, spleen, thymus, and blood (Kohn,
2001).
The first HIV-1 Tg rat contained a transgene that consisted of an HIV-1 provirus deleted for gag and pol. In order to model gene expression in an infected human, Reid and his colleagues used the viral LTR to aid in regulation of the transgene, allowing its expression in the
same tissues as during a human infection. The viral genes were expressed in lymphoid tissues of
Tg rats, which is quite comparable to infected humans. Cyclin T is a protein required for LTR
regulation. It was found that rat cyclin T is functional, while mouse cyclin T is not, so this may
explain in part why the HIV-mice were not a valid model (Reid et al, 2001). Furthermore, in this
study, rats were better to use than mice because rats provide about ten times more blood than
mice and have larger organs for larger tissue samples (Kohn, 2001).
24 ANDi
Anthony Chan, Gerald Schatten, and colleagues at the Oregon Regional Primate
Research Center (Chan et al, 2001) wanted to create a transgenic monkey because monkeys are more closely related to humans than mice (Lemonick et al, 2001). The transgene they used was the green fluorescent protein gene from a jellyfish that glows green under blue light (Vogel, 2001). This protein is helpful in scientific research because it allows scientists to look into the Figure 6: ANDi the first genetically altered inner workings of cells. The green fluorescent protein (GFP) has also primate (Vogel, 2001). been inserted into numerous other species including plants, frogs, and mice (Vogel, 2001). Chan and colleagues injected a modified virus into 224 unfertilized rhesus-monkey eggs. They fertilized the eggs by microinjection of sperm, which resulted in the growth of 126 eggs. From those 126 eggs, they chose forty embryos and implanted them into twenty female monkeys. As a result, five pregnancies occurred and three monkeys were born, but only one monkey (Figure 6), named ANDi for “inserted DNA” backwards, showed any signs of the transgene (Begley, 2001).
ANDi is the first genetically altered primate ever created. Although this particular transgene is harmless, and served as a test to see if a transgenic primate could be created, other transgenic primates may follow in the future.
The monkey does not glow bright green, but traces of the gene were found in some of the monkey’s cells including muscle, hair, cheek, and blood cells (Lemonick et al, 2001). One of the pregnancies previously stated included a set of twins, which is a very rare occurrence with monkeys. These twins miscarried, but unlike ANDi, their hair follicles and toenails did glow green under proper lighting (Vogel, 2001). The next step in the study is for ANDi to reproduce to see if the transgene is in its reproductive cells (Lemonick et al, 2001). Even though monkeys
25 are more closely related to humans, they do not reproduce quickly, they are expensive, and there are many ethical questions surrounding their use in research, including the fact that some primate species are facing near extinction. However, if certain techniques are perfected they could prove to be invaluable in the study and understanding of many human diseases (Lemonick et al, 2001).
Parkinson’s Fly
Parkinson’s disease is a gradual neurodegenerative disease. It is described by the slowing of voluntary movements, muscular rigidity, postural abnormalities as well as tremors. The disease is progressive and neurological, and is ultimately debilitating. Its main target is people over the age of fifty, but at least ten percent of the cases occur at an earlier age (Medical
Information Organization, 2004). The disease is characterized by a loss of dopaminergic neurons in the substantia nigra area of the brain (Adams, 2004).
Through different studies, over-expression of wild type mutant “α-synuclein” has resulted in selective breakdown of dopaminergic neurons in transgenic Drosophila flies (Feany and
Bender, 2000). α-Synuclein was a logical choice for transgene since mutations in the gene are linked to human Parkinson’s cases, and α-synuclein accumulates in Lewy bodies, a characteristic of the disease (Adams, 2004).
In addition, the discovery of mutations in the gene “parkin” associated with autosomal recessive juvenile Parkinsonism has helped researchers learn more about the pathology of
Parkinson’s disease. Numerous point mutations and deletions in parkin have been identified as associated with the disease. However, the actual function of parkin is unknown. Research has suggested that parkin acts as a component of E2-dependent ubiquitin ligase (enzyme) activity.
26 Misexpression of wild type and mutant proteins has been successful in the study of certain aspects of Parkinson’s disease (Jackson, 2004).
George R. Jackson of the David Geffen School of Medicine at UCLA has created transgenic Drosophila expressing both wild type and mutant “DRIR parkin”. Flies that express
DRIR parkin in its neurons show progressive neurodegeneration and abnormal behavior that is similar to human Parkinson’s disease such as decreased coordination. While the effect of mutant parkin seems to be profound, wild type parkin seems to have no effect.
Studies are continuing, and Dr. Jackson and colleagues are currently working on a fly to quantitatively study abnormal parkin-induced motor changes that will allow for easier genetic and chemical screens for the disease (Jackson, 2004).
Transpharmers
The second class of transgenic animals is called transpharmers. These animals are used to study the production of a pharmaceutical protein or antibiotics in their milk (GM
Pharmaceuticals, 2001). Ultimately all transpharmers are female because males cannot produce milk. Transpharming results in easy product purification, low production costs, and eliminates the need for drug refrigeration. Some medicines that are used in certain treatments for human diseases require biological products, and the cell culture method is frequently used to produce many of these products. However, a limited amount of product results from using the cell culture technique, and purification is much more difficult (GM Pharmaceuticals, 2001).
With the transpharming method, the researcher inserts the gene for the product into the animal. The product is produced within the breast epithelium and then is secreted in its milk
(Adams, 2004). By using this method, not only is purification made easy, but production is also
27 increased and the protein or antibiotic can be left in the animal’s milk and administered (Adams,
2003). On the other hand, this technique is possibly only useful for certain drugs.
Genzyme Goats
The well known pharmaceutical company, Genzyme, genetically altered goats to produce human antithrombin III (hAt), (Baguisi et al, 1999) which is a serum glycoprotein. It controls blood clots (i.e. it acts as an anticoagulant) by inactivating the clotting factor thrombin as well as inhibiting other clotting factors trypsin and chymotrypsin (Phadke et al, 1998). This serum
glycoprotein is very useful for those people who need anticoagulants such as patients undergoing
surgery.
The DNA of the human antithrombin III gene was injected directly into the oocyte by a
procedure called somatic cell nuclear transfer (Baguisi et al, 1999). The DNA includes a
promoter for the milk protein and therefore the hAT is secreted in the animal’s milk (Goldsmith,
1999). Through transpharming, the gene becomes a part of the goat’s genome, which allows for
the goat’s offspring to also inherit the gene. Then the female offspring can be milked and a
successful transpharmer carries the hAT serum glycoprotein in its milk. When the goats were
two months old, the first CFF6-1 goat went through a two week hormonal lactation-induction
protocol. Once the treatment was completed, milk samples were collected for thirty three days.
When the milking was discontinued, the volume of milk had increased to ten milliliters per day.
Next the concentration of hAT in the samples was examined. High levels of rhAT (the transgenic
form of hAT) were detected using the western blot analysis. The CFF6-1 goat milk was observed
to contain a concentration of 5.8 g/L of rhAT at day five, and 3.7 g/L at day nine (Baguisi et al,
1999). Therefore, these studies have shown promising results.
28 Sheep
In 1963, the alpha-1-antitrypsin deficiency was discovered that greatly affects the lungs
and respiratory functions. In the past and even today, many people affected remain unaware that
they have the deficiency until their middle to late thirties. The median age of survival is about
fifty-four years of age for a person who is a victim of this deficiency (White, 1999). Scientists
soon realized that this would be a great problem to tackle with a transpharmer.
Alan Colman (Ezzel, 1991) of PPL Therapeutics created the transgenic sheep expressing
alpha-1-antitrypsin, which is also known as AAT (White, 1999). AAT is a
protein produced in the liver, which protects the lungs, stimulates an Figure 7: The logo of PPL enzyme that fights bacteria, and gets rid of dead lung tissue to keep the Therapeutics, a company, which has played an lungs functioning properly. Permanent lung damage is a possible important role in the creation of transgenic animals (PPL Therapeutics, 2004). result for a person lacking the right amount of this protein and these
people are also vulnerable to emphysema. These transgenic sheep could provide an affordable
treatment for the estimated 100,000 American patients with the deficiency (White, 1999). The
current source of this protein is through blood plasma donations, which can cost as much as
$80,000 (White, 1999). These sheep are treated with great care and they are quarantined so they
are not as susceptible to infections or diseases (White, 1999). As of now, this transpharmer is responsible for the only FDA approved drug to date (Adams, 2003).
Baby Herman
Lactoferrin is a glycoprotein antimicrobial agent which belongs to the iron transporter family. It was originally isolated from bovine milk. This protein is multifunctional and has many biological roles, which include the source of iron for breast-feeding infants. It also seems to have
29 antibacterial, antifungal, anti-inflammatory, antioxidant, and immunomodulatory activities (PDR
Health, 2004). Without sufficient amounts of lactoferrin the body could lack in many of these
important activities.
In 1990, two cows were born after Herman de Boer at Gene
Pharming Europe, collected cow eggs from his slaughter house and
implanted embryos with the gene to produce lactoferrin into female
cows. However, of the two cows born, only one bull named Herman, Figure 8: Baby Herman, the world's first transgenic bull, showed signs of the lactoferrin transgene (O’Brien, 1998). Herman was and his daughters who carry a human gene for deemed the world’s first transgenic cow, which was quite a remarkable creating lactoferrin- enhanced milk (Pharms of the Future). accomplishment because cows have been said to be very difficult to
make transgenic because of their large size (Adams, 2004).
Scientists were enthusiastic and wanted to make sure the experiment was a success, but
Baby Herman was a male so he could not produce the protein. He was then bred with a normal
female cow, and four years later Baby Herman’s first female daughter was milked. Research
showed that the milk of the female offspring did contain lactoferrin and therefore the experiment
was indeed a success (Adams, 2003).
Kg of milk per Species Transpharming Success year Mouse ? tPA: clot dissolver drug uPA: clot dissolver drug (Urakinage) Pig 320 Human Hb (Hemoglobin) Sheep 1800 AAT: alpha-1-antitrypsin Only FDA approved drug Goats 2700 tPA Cows 9000 Lactoferrin: kills bacteria; Baby Herman Table 1: Transpharming Transgenic Animals. Above is a chart showing the number of kilograms of milk certain animals produce per year. It also shows medical successes of transpharmers (Adams, 2003).
30 Xenotransplanters
Xenotransplanters are animals altered to grow human-compatible organs for animal to
human transplantation (Pearson, 2001; Butler, 2002). These organs are more human-like because
they lack certain animal proteins that normally cover the organ’s surface. As a result, rejection is
reduced. Scientists have been focusing their studies on using baboon and pig organs for these
types of transplants (Butler, 2002) because their physiology is similar to humans. Three animal
to human transplants have been attempted using baboons. Unfortunately, all three failed.
In 1984, a baby died just twenty days after surgeons in California transplanted a baboon heart into her body (Schaefer, 1995). Less than a decade later in 1992 and 1993, two patients died within ten weeks of receiving baboon livers (LifeTIMES Magazine, 1997). As a result of these failures, doctors and scientists have realized that baboons are not the number one choice for animal to human transplantation, and guidelines have been issued by the FDA (Logan and
Sharma, 1999; Schaefer, 1995).
The transplantation of regular animal organs into a human will almost definitely result in rejection of the organ because the human immune system identifies the cells as foreign. The cells are destroyed by T-cells and therefore the transplanted organ will not function properly. These transgenic animals will no longer produce the animal specific proteins that will bring about the detrimental immune response and rejection (Kaiser, 2002).
Pig Xenotransplanters
The original xenotransplanter pig was created by PPL Therapeutics. Scientists inactivated the gene for the enzyme 1,3 galactosyl transferase (Kaiser, 2002), which is the enzyme that is
responsible for adding the sugar, 1,3 galactosyl, to the surface of pig cells. These sugars are
31 specific to pigs so in turn they trigger rejection in humans (Butler, 2002). By removing the sugar,
the organ is more compatible to humans so rejection is less likely (Kaiser, 2002). Although the
sugar has been removed, there are actually two genes for this sugar so some sugar from the other
gene is still present. The next necessary step is to breed the pigs to produce offspring that will
not produce the sugar at all. This scientific study holds some concern because rejection can still
occur when T-cells recognize other foreign antigens, and the possibility of the spread of diseases from animals to humans must also be taken very seriously (Butler, 2002). Also pigs make up a good percentage of our food resources so scientists need to prove that, by removing the sugar, they are not contaminating the pork.
Food Sources
Food sources fall into the category of “super” animals, which are given this generic name to describe their size. These transgenic animals are genetically engineered to produce more meat, so fewer animals are killed for the same amount of meat. They are also sometimes referred to as
Frankenfoods (Adams, 2003). By inserting a growth hormone gene these animals grow both larger and faster. But, bigger does not always mean better. “Super” animals may not adapt to their size and as a result there could be harmful consequences to the animal’s health including the development of arthritis, ulcers, kidney disease, and reproductive problems (Adams, 2004).
At this point, no transgenic animals have been approved by the FDA for use as human food
(Matheson, 2004).
32 Superpig
Superpig was created by a scientist named Vernon Pursel, who researched growth hormones in pigs. Pursel’s ultimate goal was to create a pig with more meat and less fat. He hoped that his study would be helpful to the pork industry and consumers. His most notable research was when he took an ovine growth hormone fusion gene and put it into pig zygotes
(Pursel et al, 1997). He was able to produce a dozen pigs, and each showed a different amount of the growth hormone.
Pursel’s study seemed to be running smoothly, but then the study turned into large disaster (Adams, 2003). The problem was the growth gene was not targeted to any specific area
of the pigs so the pigs did have more meat but also larger organs including livers, kidneys, and
thyroids. Superpig suffered greatly compared to normal pigs (Pursel et al, 1997) in that it got
horrible arthritis (Adams, 2003). In his research, other types of growth hormones were also
tested, but history repeated itself because the hormones are difficult to regulate and it is hard to pinpoint exactly how much of the hormone the pig will produce (Pursel et al, 1997).
Superpig endured great pain and had to be quickly put down. The experiment was then halted (Adams, 2003). These transgenic animals are very experimental and they may become valuable asset for more food for the poor or impoverished countries if techniques are improved.
Superfish
Superfish has been attempted using quite a few different types of fish. In a study conducted by Robert Devlin and colleagues, rainbow-trout eggs obtained from a very slow- growing wild strain were microinjected with a salmon growth hormone. The transgenic trout grew much faster than normal trout. Although these trout were considered Superfish, their
33 growth still could not match that of a fast-growing normal domesticated strain of trout.
Interestingly, these scientists discovered that if they inserted the growth hormone into these fast-
growing trout, they did not grow larger or faster meaning that the effects of the transgene were
not always additive (Devlin et al, 2001).
The transgenic wild strain rainbow-trout have a similar build to the normal trout but their
size at maturity can be affected by the growth hormone and this is
something that concerns these scientists. Their studies have shown
that domestic and wild-type transgenic trout experienced decreased
viability and cranial abnormalities. Also, domestic transgenic trout
all died before they fully matured. It seems that the effect of
inserting a growth hormone into the fish is “dependent on the Figure 9: The variations in size between control domestic and wild rainbow-trout, and degree to which earlier enhancement has been achieved by genetically engineered domestic and wild rainbow- traditional genetic selection” (Devlin et al, 2001). Through this trout (Devlin et al, 2001). study it is clear that many aspects, such as the strength of the gene, need to be considered when trying to enhance agricultural animals (Devlin et al, 2001).
At the opposite end of the spectrum, a successful transgenic food source was accidentally uncovered about two decades ago. Choy Hew froze a tank full of flounder and thought he had killed them. However, flounder have a gene that activates a protein to keep the fish alive in cold water. Hew and colleagues were able to isolate the gene and attached it to the growth hormone
of a Chinook salmon. They chose the salmon because it lives in cold water so the idea was that
the Superfish would grow much larger than normal Chinook salmon. Instead the fish appeared to
grow about twice as fast as its normal counterpart while maintaining its traditional size.
34 Superfish reaches its full size in about eighteen months versus twenty-four to thirty months
(Hew, 2000).
Biological (Scientific) Models
The fifth category of transgenic animals is used to study biological development because
not every function of every gene in the human genome is known. Transgenic animals of this kind
contribute to the study of what happens to genes as function is increased, decreased, or
completely shut off. Biological models make it easier to look at the functions of genes and what will happen if they are altered. They also help scientists study how genes are regulated, and how they affect functions and development of the body (Adams, 2004).
Doogie
In 1999, Tang and colleagues created a “smart mouse” named Doogie. These researchers from Princeton University created the transgenic mouse by a pronuclear technique. This approach called for the insertion of non-circular DNA, which contained the gene that over
expressed the N-methyl-D-aspartate (NMDA) receptor subunit
NR2B, into inbred zygotes (Tang et al, 1999). The goal of creating
the mouse was to see if an increased expression of the subunit of
the NR2B NMDA receptor would improve learning and memory Figure 10: A “Doogie” mouse tries his luck during a learning and memory test (Tang et al, 1999), which is something many people would love to (Harmon, 1999). increase.
Quite a few things are known about this receptor including that it is made up of two
subunits including NR2B, it is located on the membrane of synapses, and it binds glutamate as a
35 neurotransmitter (Bliss, 1999). The function of NR2B was the basis for this study because it is
the most important subunit in glutamate binding and it is similar to a gateway in learning and
memory (Bliss, 1999). Studies have shown that learning is enhanced when calcium (Ca++) floods
the cells after the glutamate binds to the NMDA receptor and the membrane is strongly
depolarized (Bliss, 1999). Tang and colleagues found that by over expressing the receptor and its subunit, Doogie was able to learn faster and remember longer (Harmon, 1999).
Each of the preceding categories contains a number of notable examples. However it is now our turn to decide which are ethically acceptable and which are not. As previously stated each example has made contributions scientifically, culturally, and socially. In the next chapter, we will explore different views on the topic of transgenic animals and try to decide which examples will have a positive effect on our future.
36
CHAPTER 3: TRANSGENIC ETHICS
Marcella Corcoran and Whitney Moore
Previously, we were able to categorize and describe many notable examples of transgenic
animals. Now that scientists know how to create these animals, the next question is should they?
After researching the ethical pros and cons behind these genetically altered animals, we have
encountered a mixed response. People who disagree with the idea of engineering these animals
believe that it is unnatural and scientists are trying to play God. On the other hand, others counter
this argument with the medical benefits that these animals produce and the future successes they may hold.
With biological advances such as these transgenic animals, we must consider all the ethical debates, both positive and negative, that surround them. We must choose right from
wrong and decide when and if it is acceptable to sacrifice an animal’s life for that of a human. In
the following chapter, we will try to cover many questions, which include should life be manipulated? We need to consider the life of the animal even though medical achievements are reached for humans. Also, what makes it right to manipulate an animal over a human? In a recent book review on Animal Rights by Peter Singer, influential activist, Dave Kopel, argues that a
mentally retarded child has rights but limited intelligence, whereas certain animal primates have no rights but a very high intelligence, even higher than that of the child (Kopel, 2004). We would consider the child’s rights violated if we were to submit him or her to poking with an electric cattle prod. So the question is why don’t we consider an animal’s rights violated too? Animals do
37 not communicate on the same level as human beings therefore how do we know exactly how they feel about their treatment?
Other ethical questions include the ultimate goal of creating these animals, and why are humans considered most superior? Genetic engineering of this kind can only be used for the right purposes because if it were to fall into the wrong hands, the results could be catastrophic. The
goal of this chapter is to investigate transgenic animals as well as legal and ethical decisions
concerning them. We will discuss the controversy behind them, their effect on science and
society, and hopefully determine when the creation of these animals is acceptable and when it is not.
Hunting for Pleasure vs. Sacrificing for Medicine
When considering the ethics behind transgenic animals, we must consider society as a whole and the many different viewpoints that arise on certain subjects. One subject that can be considered is that of hunting. Certain state legislations have passed laws permitting hunting and
the times of year when it is allowed to take place. Hunting is defined by Webster’s Dictionary as
“to kill or catch game for food or sport” (Neufeldt, 1995). The game they are referring to is in
fact animals, and to kill means to terminate their life. People hunt for pleasure, and kill whatever wildlife they see that is on the permit. On the other hand, scientists carefully pick their subjects, segregate them from the rest, and keep them under close watch. Hardly ever do they go into the testing with the intent to kill the animal unless it is to harvest their organs to save human lives.
With hunting, the competitor enters the sport with the intent to kill an animal. “Hunting” even occurs seasonally in our own homes as we set mouse traps to kill pesky rodents.
38 Considering the act of hunting versus the act of creating transgenic animals provides us
with two totally ethical opposites. Legislature creates laws allowing hunting, but they also create
laws and guidelines against the creation of transgenic animals. Transgenic animals are not
always sacrificed. In the case of the Alzheimer’s Mouse, the animal is not injured in any way and
has a large medical benefit. Whereas with hunting, the sport is defined by the amount of game
killed, which provides enjoyment. So for society to allow the “game” of killing animals as a
sport, and to restrict creating transgenic animals, which can serve an actual medical purpose, this
is an ethically confusing stalemate. Yes, transgenic animal production has its risks, but in most
cases the animals do not experience any severe suffering, and we must also consider the overall
positive medical human benefits. On the other hand, with hunting there are no benefits to
humans whatsoever, except to have something to hang on the wall to be proud of. The question
is which is more rewarding; in some cases killing animals to in turn save many sick humans, or killing animals just for fun? Therefore, ethically, society should take a look at the big picture,
think about the technology, and become more open and aware of transgenic animals and the
positive benefits they offer.
Transgenic Animals Are Unnatural
Many may disagree with the altering of animal lives, and view it as “unnatural”. Little do
we realize that genetic engineering has been present throughout history. Humans have been
altering life without even knowing it. For example, people have been paying large sums of
money for dogs that have been bred for desired characteristics. This is altering animal life, and
people have not seen anything wrong with that. Another example is the discovery of genotype
and phenotype, where scientist Gregor Mendel crossed different species of pea plants. With this
39 cross-breeding, he created a new species and discovered the alteration of genes (O’Neil, 2003).
Altering animal’s lives has changed technology and allowed our world to advance. Genetic engineering should be accepted by society since most of the alterations provide human benefit.
Looking at the medical world, prosthetics are greatly in use as well as blood transfusions, antibiotics, and new methods of birth control. Taking a step back, these medical advancements have actually altered human life to make it better and allow people to live happier, healthier lives. So far, the good outweighs the bad in such alterations. This is the same with altering animals. The main purpose for these experiments is improving the quality of human life, no matter what it takes. If we have been doing it throughout time, why should we suddenly care now?
Religious Aspects of Transgenesis
People may support the creation of certain transgenic animals, but are heavily persuaded by their religion, which for many people, plays a large role in their lives. For example, in the
Christian faith, Man is given the right by his creator to alter creatures. God has given Man the power to make such a decision and change creatures for beneficial purposes. If one thinks about it, how can the world have started with just a snake, a man, and a woman? Something had to be altered to create all of these different species of animals, plants, and humans. Also, Man was the first thing created when God created the world. Therefore, since Man was the basis of early society, he should then have the power over all creatures as he is considered the Supreme Being
(Loma Linda University, 1997).
The Holy Bible believes “It is a Christian responsibility to prevent or relieve suffering whenever possible” (Acts 10:38; Luke 9:2). With the creation of disease models, such as the
40 OncoMouse™, studies have lead to determining human oncogenes. Because of these models we are now able to alleviate pain and suffering in human cancer patients, and aid with other diseases including Alzheimer’s disease. The Holy Bible also states: In all of God's creation, only human beings were created in the image of God (Genesis 1:26, 27). Therefore, humans should live longer, healthier lives, making it acceptable by Christians to try to alter animals to improve human life (Loma Linda University, 1997).
In the Catholic faith, it is a strong belief that we should shape creation for widespread benefit. Therefore, as we create prosthetics and artificial skin, the purpose behind it is to aid in improving human life. Catholicism shares similar views with Christianity. Both religions are more in favor of transgenic animals rather than opposed.
The faiths of Islam and Judaism allow the use of animals to be altered for positive effects on human life and health. As quoted by the Muslim scholar, Sheikh Yusuf Al-Qaradawi, “One of the blessings of Islam is that it never abstracts scientific programs or narrows the scope of the mind in the field of science and technology. Unlike other religions, there is no conflict between science and religion in Islam,” (Islam Online, 2003). On the other hand, Hindus believe cows are sacred and it is against their religion to consume any cow meat. Hinduism, along with Buddhism, supports the alteration of animals as long as they are handled “compassionately” by transgenic methods (Adams, 2004). Such religions may not be in favor of models like Superpig, where there is no clearly defined medical benefit to society, but most definitely the Alzheimer’s Mouse and other models where there are medical benefits to society without imposing pain or suffering.
41 In the case of transgenic animals, it is not enough to just lump them together in one giant
group called transgenic animals. Each of the five subgroups must be examined, and even then, each example within the subgroup must be studied case by case.
Disease Models
Animals in this group are genetically engineered to closely mimic human diseases that include Alzheimer’s disease, cancer, HIV, AIDS, and Parkinson’s. These animals make drug or vaccine testing possible where it could be dangerous and potentially fatal for humans. As a result of the alterations to the animal, scientists essentially make a healthy animal mimic some aspect of a human disease. On the other hand, where no “naturally occurring” animal models exist, creation of a transgenic disease models may be necessary to study disease processes, progress, and treatments (Noonan, 2003). As a result, some of these models hold great medical benefits with little to no suffering, while others have medical perks but much pain and suffering is observed (Adams, 2004).
Alzheimer’s Mouse
Currently Alzheimer’s disease affects 4.5 million people in the United States alone. It is
predicted that by 2050, this progressive, mind-erasing disease will be the fourth leading cause of
death, and affect approximately 16 million people in the United States (The Fisher Center for
Alzheimer’s Disease Foundation, 2004).
The Alzheimer’s Mouse line was created by Professor David Adams and his colleagues
at Athena Neurosciences Incorporated (formally known as Exemplar Corporation, Waltham,
42 MA; which was formerly TSI Corporation, Worcester, MA) (Games et al, 1995). These scientists inserted a gene in embryonic mouse cells for Alzheimer’s disease. At approximately six to nine months of age, the mice developed plaques similar to those found in humans suffering with the disease (Games et al, 1995; Schenk et al, 1999). Although plaque-generating, these mice showed no signs of pain or suffering, and only performed slightly slower on a maze test (Adams, 2004).
Therefore, Alzheimer’s Mouse holds little negative ethical consequences.
This animal line is extremely beneficial because it is absolutely necessary for the next step in finding a cure for Alzheimer’s disease. Orangutans are the only animal that naturally gets
Alzheimer’s disease, and it takes them 60 years to get it as with most human cases. Without this mouse line, little advancement would probably be made in the study of this disease that affects so many families (Adams, 2004). This disease model has such potential that it was used to create and test the first vaccine for Alzheimer’s disease by Elan Pharmaceuticals in 1999 which is currently in phase-II of human trials (Schenk et al, 1999).
OncoMouse™
Philip Leder and colleagues created the OncoMouse™ with the intent to help cancer patients worldwide by determining which genes cause cancer, and which drugs can block oncogenesis. This is exactly what the OncoMouse™ line of transgenic animals achieved.
OncoMouse™ ethically falls into the “grey area” because these animals can suffer if the tumors are allowed to grow to full term, and if no pain medication is used. But it provided many medical benefits. We must look at the big picture of why the OncoMouse™ line was created.
The medical advancement was huge by inducing the mouse with human cancer because it
43 provided a chance to identify the cause and help find cures for cancer without using a human model (Society, Religion and Technology Project, 2001).
Although the mouse can suffer, we must also consider the lifespan and breeding habits of
mice to help determine the benefits of the model. A mouse at one year of age is equal to that of a
middle aged person (Leder, 2003). They have a much shorter lifespan than humans, which makes
them easier to study. Also, when a mouse reproduces, it experiences a shorter gestation period
and it produces a larger litter. This fact means mice can make progeny in a much shorter time than humans. This also allows for a larger subject test pool to make sure the results of a test drug
are reproducible. Therefore the results can be quite accurate (Noonan, 2003). One must consider
these facts about mice when one thinks about the ethics of this experiment.
The OncoMouse™ can be compared to Superpig along the lines of animal suffering and
being forced to be put down. It is important though that the two animals are compared. Superpig
was created as a food source with the intent to allow humans to eat more healthily and kill fewer
animals for the same amount of meat. On the other hand, OncoMouse™ was created to study
cancer, how it affects the body, and to screen potential drugs, which could bring scientists one
step closer to a cure (Adams, 2004). Examining which animal is more beneficial to humans
today, the OncoMouse™ definitely takes the cake. By studying similar symptoms between
mouse and human cancer patients, it allows us to better understand and treat the suffering and
symptoms of human cancer patients. What other animal would make studying ethical? None.
The best way to study cancer isn’t through a book or research; it is through experimenting and
seeing the symptoms and behavior of an affected patient. That’s why the OncoMouse™ is so
valuable. Scientists are able to get a first hand glimpse of what it is like to have cancer and all the
genes that collaborate together to cause the disease (Leder, 2003).
44 The OncoMouse™ may have strong ethical considerations, and is ethically unaccepted by many people, and even countries have tried to stop it in its tracks (Check, 2002) but in our opinion, its positive research has outweighed all the negatives, especially when strong oversights are used to help minimize the animal’s suffering. Painkillers or other drugs can be used to minimize pain, or the animal can be sacrificed before suffering becomes too extreme. The
OncoMouse™ had been researched thoroughly before the whole plan was put into action. The authors of this paper support the creation of the OncoMouse™ as the information it has already provided is immeasurable.
ANDi
ANDi, created by Anthony Chan, Gerald Schatten, and colleagues at the Oregon
Regional Primate Research Center (Chan et al, 2001), was the first genetically altered primate
(Vogel, 2001). ANDi’s close relationship to humans makes experiments concerning primates both promising and troubling (Lemonick, 2001).
First, we should note that ANDi (which stands for “Inserted DNA”, backwards) is transgenic for a jellyfish gene that encodes green fluorescent protein. This is a harmless gene whose protein product fluoresces green, so it is used to locate the tissues expressing the transgene (Adams, 2004). So although ANDi is the world’s first transgenic primate, he was not created for human medical benefit himself. But hopefully the technology will be used in the future to create other models. As a result of creating transgenic monkeys, lives could be saved and researchers would be given a powerful tool for studying, possibly treating, and hopefully someday curing, painful and deadly human diseases (Lemonick, 2001). Richard Weleber, a professor of ophthalmology at Oregon Health Sciences University says, “this is a revolutionary
45 achievement,” and he believes research with primates like ANDi could help cure macular degeneration, a form of blindness (Lemonick, 2001).
Experiments with ANDi however, also raise disturbing questions having to do with
animals rights, as well as how far genetic manipulation can be allowed to go. As scientists wait
to see if ANDi’s offspring inherit the GFP transgene in their genome, it is unsettling for many
people to think that scientists will have created an entirely new line of transgenic primate
descendants, and as this germ line gene engineering is accomplished in primates, the technique
will become one step closer to being attempted in humans (Lemonick, 2001).
“If he were human, he’d be called a designer baby”, says Sharon Begley about primate
ANDi. “At some point in the future,” admits Anthony Chan, “it is conceivable that others may
attempt this technique to enhance humans” (Begley, 2001). Genetically altering human eggs so
that a disease-causing gene is replaced by a healthy gene could help a fetus or a family lift a
family curse of cancer, atherosclerosis, schizophrenia, or possibly another disease with a strong
genetic component. It could also allow a family to choose the hair and eye color of their unborn
child (Begley, 2001). However, some believe that nobody is likely to try to play God with
humans like this for years to come. A few reasons for this may be because ANDi has proven that
it is very difficult, expensive, and more importantly, hard to predict the unexpected side effects a
transgene can bring to the table (Lemonick, 2001). Also as Arthur Schafer of the University of
Manitoba warns, “It has taken millions of years to evolve; should we really be changing it in a
generation or two?” He also has qualms about the evolution of new social divisions. As of now
society has the “haves” and “have-nots”. If transgenic humans are created, society will have the
“gene-rich” and the “gene-poor” (Begley, 2001).
46 The writers of this IQP believe that a transgenic primate is an incredible accomplishment,
but primate genetic techniques must be perfected, and it must be used for the right reasons.
Transgenic primates could definitely aid scientists in studying pathways, cures, and treatments
for human diseases because primates and humans are so closely related. But it is our opinion that
society must not become careless and greedy. In the future, if these primates result in the ability
to rid human families of genetically predisposed disease curses, that would be a wonderful feat,
but experiments conducted with ANDi and his offspring should not permit humans to pick the
hair and eye color of their offspring just because they see blonde hair and blue eyes as beautiful.
Transpharmers
Transpharmers, animals that are genetically altered to secrete pharmaceutical proteins or
antibiotics in their milk, are nearly controversy free compared to other classes of transgenic animals. Very few ethical or animal welfare problems are raised for this class, and a strong positive ethical case can be created.
Transgenic animals in this category are beneficial to humans, with only a slight intervention that does not degrade the animal’s integrity (Society, Religion and Technology
Project, 2001). Other advantages include easier product purification than traditional mammalian
cell culture, low operating costs, unlimited breeding, and high production. Even more
importantly, there is no animal sacrifice, no signs of animal suffering, and the produced protein
drugs retain complete bioactivity, meaning all post-translational modifications can occur
(Adams, 2003).
On the other hand, some problems that are encountered include low stable transmission to
offspring, and occasionally low drug yields (Adams, 2003). It could also be argued that creating
47 transpharmers “as living bioreactors for pharmaceutical production is an instrumental way of using the mammary function of the animal” (Society, Religion and Technology Project, 2001).
Hindus are especially against this type of tampering with life in reference to transpharming cows.
This religion argues that cows are sacred, and by genetically altering them, even though the cows
do not suffer, and are unaware of the treatment, they consider it unacceptable. Transpharming is
also considered unacceptable to the Hindu’s and other animal rights activists if the animal’s
metabolism is changed in any way, or if a protein is expressed in any non-mammary tissue that
could cause damage (Society, Religion and Technology Project, 2001).
Animal milk has been used as food by humans since humans first walked the earth. Ever since then, humans have intervened in the animal’s daily lactation, and have selected by traditional breeding, animal strains that produce more milk. As a society, we already use chemicals in most dairy products, including cheese and yogurt so that humans may consume them. These types of alterations are not deemed as ethically unacceptable (Society, Religion and
Technology Project, 2001) and therefore the writers of this IQP consider transpharmers as acceptable transgenic animals.
Xentotransplanters
As the need for transplant organs increases with each passing year, something must be done to solve this demand. As researched by the American Heart Association in 1997, only 2,300 of the 40,000 U.S. citizens who needed a heart transplant received one. Around the same numbers are represented by other organ demands as well (Mooney, 1999). With the usage of xenotransplanters, harvesting animal organs for humans, we allow for more off-the-shelf availability of organs, and we would decrease the vast demand for organs. We would also be able
48 to raise animals solely for the specific organ desired, which would then allow for the best care to
be given to the animal and organ. Pigs are currently a large focus of study for this purpose, and
have shown promising results. Scientists are presently working on reducing the sugar coating the
pig produces on their organs to decrease immuno-rejection once transplanted into a human
recipient (Butler, 2002). Even though scientists are trying to eliminate rejection, it still is always
a risk we must be willing to take.
Previously, baboon organs had been used, all of which eventually failed. They were valiant efforts for desperate patients, but unfortunately, the body rejected the organ as a foreign item, even when using immuno-suppressive drugs. Even though baboons are similar to humans, the compatibility must be altered more than scientists had expected in order to prepare the organ to be readily accepted by a human host (Kaiser, 2002).
On the downside, xenotransplants must be carefully screened for any strains of disease or viruses unique to the animal donor, which can then be passed onto the patient receiving the organ and can lead to either patient rejection or causing a new strain of virus as it grows in the patient.
We must also consider the possible strains of disease that are present but still in a dormant state in the animal’s body. For example, with prions, the cause of Mad Cow Disease, it was present in the cow’s neurological tissue for an extended period of time, just in a dormant state. The same risk is present in the sharing of organs from animal to human.
Although many people agree that xenotransplanters are valid for the heart and kidney because of the lack of donor availability, they should not be “carte blanche” for all organs.
Objections may increase with these transgenic animals as repeated failures occur and breakthroughs continue in artificial hearts (Society, Religion, and Technology Project, 2001) such as the promising, mechanical AbioHeart. With the invention of a mechanical heart, it is
49 more easily monitored and avoids animal sacrifice, possibly making it more ethically accepted by society.
Xenotransplantation has the potential to greatly benefit society. Ethically, this class can be compared to transgenic food sources, because the animal is being created for the sole purpose of sacrifice for the benefit of humans, and alternative sources may exist. Yet we must outweigh the negatives and look at the great impact it would have on ill, waiting patients. The authors of this paper support xenotransplantation because it would greatly aid in the increasing demand of organs our nation has always had to deal with, providing the animal donors are carefully raised, and screened for known harmful viruses.
Food Sources
When considering the transgenic animals created for improved food sources, such as
Superpig, this class has both ethical advantages as well as disadvantages. Physically, the
Superpig turned out not so super after all. This porcine line contains human growth hormone as a transgene, and was created to grow larger pigs with leaner pork for consumption. The growth gene was not targeted to any specific area of the pigs so the pigs had more meat as Pursel had planned, but there was also an increase in size of the pig’s organs, as well as suffering from arthritis and other ailments (Adams, 2003). This pig unexpectedly suffered greatly as compared to a non-transgenic pig (Pursel et al, 1997). Scientists had not accounted for the abnormal organ sizes and were therefore forced to sacrifice the pig before the experiment could continue any further (Adams, 2003). Ethically, this pig was not as successful as scientists had planned it to be, since there was no obvious societal medical benefit. “If you want more meat, just breed more pigs” (Adams, 2004). And this model may not have been a logical choice; but we must consider
50 the attempt. The negative aspects of genetically altering the food supply are sometimes given the term “Frankenfoods”. This experiment paved the way for other scientists who had similar ideas for transgenic food sources. For example in creating Superfish (a transgenic trout with extra copies of growth hormone) (Devlin, 2001), the Superpig was a good model to follow and learn what not to do in the experiment and what to be aware of. Superfish does not appear to suffer at
all. So although the Superpig produced a negative product, its results were beneficial to the
science community, allowing scientists to learn from their mistakes.
Also, food sources can be considered beneficial in the case of helping the poor as well as
impoverished countries. It is estimated that by 2010, around 680 million people in the world will
not have contact with satisfactory food to sustain good health (Environment News Service,
2000). These people are subject to malnutrition as they are not able to afford or do not have the
proper foods available for their consumption. Therefore, by altering the food to produce certain
vitamins, less fortunate people would benefit from receiving vitamins they are not able to obtain
otherwise from normal food, such as transgenic rice which provides added vitamin A
(Environment News Service, 2000). This allows people to consume their normal diet with
added benefit and no noticeable taste difference in the rice.
With altering animals for food sources, we would not only able to eat more healthily but
allow for less slaughtering of animals. In the case of Superfish or Superpig, the sole purpose of
creating these animals is to benefit society and allow for more or the same amount of meat by
killing fewer animals. This is beneficial especially to the animal population as it is not necessary
for mass killings of a school of fish for example, if we can alter fish and increase their size so
only a few need to be killed. This would also allow for cheaper meat. One important reason for
perhaps not continuing this line of research is that the genetically created Superfish, although
51 they did indeed have a size much larger than their non-transgenic littermates, were slightly
smaller than has already been obtained by classic breeding for aquaculture purposes. So for this
experiment to make sense in the future, the sizes would have to be larger than traditionally obtainable (Adams, 2004); (Devlin, 2001).
In society, there will be arguments by both sides on the very controversial topic of
Frankenfoods. Some will say America is becoming obese and should not have the need for more
food. Others will say that we need more food and more nutrition, but what we produce will never be enough. In our opinion, society is greedy and will continue to want more than we are actually
producing. Also, society keeps changing the new diets and nutrition. For example, the Atkins
Diet was a huge hit, and then was supposedly deemed “unhealthy” so now the South Beach Diet
is in. Food habits keep changing so it is too hard to try to please the public by altering animals for consumption for the benefit of society.
The authors believe that ethically, transgenic animals used for food production is not a
wise decision since the animals can suffer, and people will just keep demanding for more and
more production. Or who knows? In the future doctors could be saying fish or pork is bad for
you in general, as there are new diets and new health crazes that arise each year. These animals
turned out to be not so super and therefore should be carefully considered before their
production.
Scientific Models
As animal models were created to understand biological development, and to test the
over-expression of newly discovered proteins, ethically, this is a very wise creation. Most of
these models are not subject to any risk or suffering since they are monitored for specific
52 behaviors, and immediately sacrificed if any problems arise. In the case of Tang’s “Doogie”
mouse, it was studied for its ability to learn and retain information (Tang et al, 1999). With the
study of this mouse model, Tang was able to determine the NMDA receptor with subunit NR2B
is responsible for increasing learning and memory (Bliss, 1999). Therefore this model proves the
hypothesis that over expressing the NR2B subunit facilitates learning and memory. We continue
to research the possibilities if we enhance this receptor in humans.
With the help of these models, who were not harmed in any way, these results are very
promising and potentially beneficial to the world of science. For example, the diagnosis of
Alzheimer’s is often delayed, assuming the loss of memory is due to old age. With the help of
scientific models like Doogie, the results scientists have obtained may be useful in altering the
NMDA receptor in humans affected with Alzheimer’s disease, possibly slowing down the deterioration of memory. The authors of this paper believe scientific models that have a clearly laid out plan for scientific benefit are ethically positive and very beneficial so they should continue to be used, so long as animal suffering is minimized.
Public View of Transgenesis
As the above examples demonstrate, the ethics of transgenic animals needs to be determined on a case-by-case basis. Altering animals often makes people weary, but when they see the possibilities that arise, they realize it is worthwhile and yields positive results to improve society. In 2000, a telephone survey of
1,000 Canadians was conducted to show the public’s Figure 12: Public Views of Cloning Sheep for Vaccine thoughts on biotechnology. Surprisingly, the public’s Production (Einsiedel, 2000).
53 opinion of biotechnology is represented by their opinion of cloning, which is evident in Figure
11. However, cloning is actually only a small part of biotechnology’s many different aspects.
Only 45% of the population “encouraged” cloning, and 44% were against it. Therefore it is a toss-up. The public seems to be unaware of the many experiments in research and base their opinion only on the recent Dolly sheep cloning experiment (Einsiedel, 2000).
Other surveys were also conducted in Japan in 1991, 1993, and 1997 to evaluate the attitudes of the Japanese people toward biotechnology. In 1997, 11% of the people surveyed had
heard of biotechnology, but still did not know
enough to make an accurate decision.
However, in 2000, this number dropped to 1%
as seen in Table 2. For example, in the case of
the OncoMouse™, many people hear what
they want to hear. Some people only hear the
Figure 12: Public views towards suffering it went through. Others see the good applications of biotechnology (Macer, 2000). in the experiment. It all depends on the background of the person and their interest in the topic. The public attitudes toward certain applications show 58% of the people surveyed are supportive of genetically engineered crops,
56% support healthier meat, and 43% that replied approved of transpharmers (Figure 12). Many disagreed with the Superpig idea, which caused much suffering and no medical benefit, just nutritional benefit (Macer, 2000).
54 Over the years, society has shown to have a change in opinion as biotechnology is
becoming increasingly more popular and
much more knowledge is available. For
example in 1997, the Japanese public
mainly associated biotechnology with
alterations in crops. Yet, in 2000, the
Japanese public associated biotechnology
with cloning and genetic engineering
(Table 2). Society also seemed more
Table 2: Thoughts that come to mind when respondents knowledgeable in 2000 since the think about biotechnology (Macer, 2000). percentage of people who had not answered decreased from 21% in 1997 to 9% in 2000 (Macer, 2000).
Most people believe that scientists support any experiment regardless of the public’s opinions. This is a false statement. Scientists’ viewpoints are actually very similar to that of the
public. Scientists often minimize negative ethical considerations in an experiment if it is proven
to provide an overall societal benefit. In the Japanese survey for instance, in the aspects of
biotechnology, there is no significant difference in the opinions of the scientists versus those of
the public (Macer, 2000).
Overall, the Japanese’s opinions were very optimistic about biotechnology (Table 1). It is
interesting to note that medical applications show more approval except for the idea of
xenotransplants, which is actually outweighed by genetically engineered crops. Awareness of
biotechnology has increased, as well as the biotechnology experiments as a whole (Macer, 2000).
55 Many groups look down on animal testing. But studying diseases in animals is helpful for
studying humans. Is it more acceptable to use a human model than an animal? Most people
disagree. So if people do not support animals being used, then what will they support? Animal
rights groups can argue the ethics of how the animal was created, treated and used, but in most cases they have no argument for the benefit it provides.
The writers of this IQP believe that transgenic animals have made, and may continue to make, extraordinary contributions to the science and social community. The authors believe transgenic experiments should show strong societal benefit and be well organized before proceeding with the experiment in order to avoid any needless animal suffering. In the case of the use of transgenic animals for food sources, the authors deem this experiment as unnecessary as alternative food sources exist, and society is always changing its food preferences, and is too hard to please. In the case of Superpig, it suffered greatly; later to be sacrificed before the experiment could be completed. The authors believe in some cases, suffering is necessary to further our studies, such as in the creation of OncoMouse™. The authors also believe that transgenic animals have produced immeasurable benefits and society must see the overall picture
before making a decision to agree or disagree with the creation of any of these animals.
56
CHAPTER 4: TRANSGENIC LEGALITIES
Nicholas Maloney and Sara Munro
One of the most controversial questions surrounding the use of transgenic animals is whether they should be patented. In fact, the debate could be expanded to include the broader question of whether any life should be patented. Because OncoMouse™ (discussed in detail in chapters 2 and 3) is the world’s first patented animal, and its legal case was one of the most complex in U.S. history, this animal will serve as the initial focus for this chapter on transgenic legalities.
U.S. and European OncoMouse™ Case and Appeals
A patent is the grant of a property right to the inventor, issued by the U.S. Patent and
Trademark Office. This property right is granted by the United States, and other nations if application is also made there, which gives the holder the exclusive right to exclude others from
manufacture, use, or sale of the invention or product. The term of a new patent is usually 20
years from the date on which the application for the patent was filed in the United States Patent
and Trademark Office (PTO). Patent property rights may be sold, assigned, pledged, mortgaged,
licensed, willed, or donated, and can be the subject of contracts and other agreements. The
owner of the patent has the opportunity to profit by manufacture, sell, or use of the invention in a
protected market or by charging others for making or using it. Also, patent rights to intellectual
properties created in the process of federally sponsored research programs are usually retained
by the contracting organization.
57 A Harvard University scientist Dr. Phillip Leder and his colleagues inserted oncogenes myc and fgf7 (that cause the proliferation of mammary epithelial cells when they are expressed) into a mouse for research purposes (Cancer: The Role of Genetic Collaboration, 2003). These oncogenes would cause the mouse to contract cancer, and then Leder and his associates could research the progression of the tumor in the mouse to model oncogenesis in humans.
In 1984, Leder and Harvard University filed their first U.S. patent on this mouse. Three separate U.S. patents were eventually awarded: Oncomouse itself (Leder and Stewart, 1984,
Patent #4,736,866), methods for deriving cell cultures from transgenic animals (Leder and
Stewart, 1992, Patent #5,087,571), and methods for assaying transgene expression (Leder and
Stewart, 1999, Patent #5,925,803). The award of these patents caused a large uproar in several animal rights and religious groups. Many appeals were filed in the following years questioning the authority of the patent due to the animal’s involvement.
In the European case, patent no. 0,169,672 (the ‘Harvard Oncomouse’ patent) was at first denied, but was eventually overturned with appeal number 1 which contained two important conclusions:
“First, it stated that while Article 53(b) of the European Patent Convention (‘the EPC’) excluded animal varieties from patentability, the fact that Article 52(1) stated that patents are available for all inventions capable of industrial application meant that this exception must be construed narrowly. Furthermore, the fact that the words ‘animal varieties’ were used in Article
53(b), rather than merely ‘animals’ or ‘animals as such’, meant that this exclusion did not have the effect of excluding animals per se from patentability. (Sharples and Curley, 2004)”
“The other important point to come out of the European Technical Board of Appeal’s decision was that the exclusion in the EPC on granting patents for inventions which are contrary
58 to morality or ‘ordre public’ contained in Article 53(a) should, in the case of a claimed invention where the animals were certain to suffer some harm, be assessed by weighing up the suffering of the animals and any possible risk to the environment against the benefits to mankind said to be conferred by the invention. This issue was referred by the Technical Board of Appeal to the
Examining Division, which subsequently decided that the benefits of the Oncomouse outweighed the risks, and granted the patent. (Sharples and Curley, 2004)”
Denial of Oncomouse Patent in Canada
Although the OncoMouse™ patent was awarded in the U.S. and Europe, the case was not so clear cut in Canada. The Canadian Patent Act controls the patenting legalities in Canada. For the purposes of OncoMouse™, two main sections of interpretation in the Act caused some controversy. The Canadian Patent Act, provides that patent protection may be acquired for any
‘invention’, defined under s. 2 as follows: “‘invention’ means any new and useful art, process, machine, manufacture or composition of matter, or any new and useful improvement in any art, process, machine, manufacture or composition of matter;” subject to the prohibition of ss. 27(3) that: “No patent shall issue for ... any mere scientific principle or abstract theorem” (Cameron,
1997).
At first, the Canadian Commissioner of Patents and the Federal Court Trial Division denied Harvard’s application for the patent on August 4, 1995. In the Canadian Patent Act, the terms “manufacture” and “composition of matter” are used. Mr. Justice Nadon was the commissioner of Patents at the time and in his opinion, and decreed the OncoMouse™ could not be an invention because he felt that the mouse itself could not be created under full control of the inventor, nor could it be identically duplicated. The commissioner also distinguished between
59 lower life forms (e.g. plants and single-celled microorganisms) (which had previously been patented in the U.S. and Canada) and higher life forms (e.g. humans and animals). He concluded that lower life forms can be patented but higher life forms cannot, and OncoMouse™ was a higher life form (Mitchell and Sommerville, 2002).
On August 3, 2000, the Canadian Federal Court of Appeal then reversed this decision by a two to one vote. Mr. Justice Rothstein spoke for the majority and concluded that there is nothing in the Patent Act that denies patenting higher life forms, and therefore OncoMouse™ can be patented. He concluded that “manufacture” and “composition of matter” should be used more broadly. He referred to a case involving Abitibi, a manufacturing company, in which a ruling allowed microorganisms to be patented. Since it was permitted that microorganisms be patented, then Rothstein believed that OncoMouse™ should be as well. Rothstein furthermore stated that the term “invention” includes objects that use the laws of nature. With this definition,
OncoMouse™ could be patented.
The main point of the new judgment was that any controllable invention that is the result of human intervention can be patented as long as it meets conventional patentability criteria of not being obvious based on prior art. As shown above, Nadon and Rothstein had different interpretations of the Canadian Patent Act. It is commonly believed that the first Judge Nadon used the law incorrectly when laying down his decision especially in regards to degree of control, reproducibility, and distinguishing between higher and lower life forms. When examining the degree of control, Nadon looked at the animal’s physical features such as eye color and ear size, when in actuality the presence of the oncogene is the object being controlled in this experiment and therefore makes it patentable.
60 As recent as December 4, 2002, the Canadian decision to award the patent to OncoMouse™
was still causing controversy. CELA, Greenpeace, CAPE (Canadian Association of Physicians
for the Environment), CIELAP (Canadian Institute of Environmental Law and Policy) and the
Action Group on Erosions, Technology and Conservation (formerly RAFI) brought their ideas
and views to the Canadian Supreme Court to attempt to reverse their decision to patent
OncoMouse™. Their main argument was for the Canadian government to maintain their
original views on not patenting living animals. This was an attempt by these environmental
groups to make Parliament review the Canadian Patent Act, using the earlier definitions of what
is patentable, as a grounds for overturning the earlier OncoMouse™ award. They presented three basic arguments to the court:
• that patents are increasingly causing barriers to the free and rapid dissemination of
science research results, and to the development of drugs, diagnostic tests and treatments;
• environmental and health risks arise from the biotechnological interventions that are the
subject of these patents;
• genetic resources are not equitably shared due to the exclusive property interest of
holders of such patents.
(Canadian Environmental Law Association Backgrounder, 2002)
After the Canadian Supreme Court heard the above views and arguments against
the patenting of higher life forms, they came to a decision. On December 5, 2002 (Case file
#28155, Harvard University vs. Canada) the Canadian Supreme Court denied the OncoMouse™ patent in a 5-4 judgment. The court said that the mouse does not qualify as an invention under the Federal Patent Act. Writing for the majority opinion, Justice Michael Bastarache said “The
61 best reading of the words of the application supports the conclusion that higher life forms are not
patentable. Higher life forms cannot be conceptualized as mere ‘compositions of matter’ within
the context of the patent act,” (Mitchell and Sommerville, 2002).
Potential Benefits of Patenting Life
There are many potential benefits to patenting transgenic animals. One of the first
benefits is the raised interest in these novel techniques in the biotechnology industry. The
increased interest is drawing more investors to the scene and providing more financial backing
for research being done. Along the same lines is another significant benefit to not only the
industry but also to the economy. During successful times, the biotechnology industry itself
creates an economic boost for all participating factions. The biotechnology industry alone brings
in billions of dollars a year for our country.
Another positive aspect of patenting transgenics is the competitive spur for innovation.
The idea of patenting mice and other animals can cause scientists to push themselves to their
highest potential so that they will obtain the patent first. This in turn will cause the scientific
community as a whole to raise the level of its work to match others. This cycle could potentially
help to exponentially increase the general knowledge of many diseases.
Potential Downfalls of Patenting Life
Canada was not the only place that held controversy over patenting animals, several
organized groups opposed it right here in the U.S. The declaration of the U.S. OncoMouse™
patent is worded: "A transgenic non-human mammal all of whose germ cells and somatic cells contain a recombinant activated oncogene sequence introduced into said mammal, or an ancestor
62 of said mammal, at the embryonic stage” (Macer, 1990). But there have been many attempts to regulate the patenting of animals and even attempts to ban them.
In regards to the OncoMouse™, there is a serious problem, not for the company who has the patent, but for all those who don’t. According to the patent, not just the original
OncoMouse™ was the property of DuPont, but also all of its offspring and subsequent generations. This is due to the fact that they all carry the same genetic makeup. Some argue this is not entirely fair to other cancer biologists because they would have to buy a mouse with that genetic makeup as opposed to creating one of them, and they need a special permit even to breed them. This could eventually cause fewer scientists to do research on the animals, and thus a slowdown of cancer research progress. This arouses the problem of secrecy throughout the scientific community. Withholding information from other scientists in regards to the “recipe” of OncoMouse™ could delay the discovery of a cure for cancer. This is not good for research because scientists could no longer work off each other and advance the studies in new and exciting ways. On a positive note, Harvard and Dupont have recently softened their stance on sublicensing OncoMouse™, allowing other universities to establish local breeding colonies.
Another major drawback of patenting animals is the idea that now other “objects” that in the past were considered non patentable, could now be overturned to patentability. Once you set a legal precedent, many more people will try to follow by using the first example as their backup.
An interesting fact in regards to patenting animals is that humans are not much biochemically different than animals. Right now there are laws restricting the patentability of humans because humans cannot be considered property. Human organs are, however, in the body of humans, just like the oncogene was in the body of OncoMouse™. These organs could
63 be genetically enhanced similarly to the mouse’s DNA. This means that in the future one could
see the patenting of humans through a precedent that began in the 1980’s with OncoMouse™.
One transgenic animal that brings up several key questions is ANDI the monkey. As
discussed in chapters 2 and 3, this animal expresses the jellyfish green fluorescent protein (GFP)
as a transgenic marker (he was not created as a disease model). Although no patent application
has been filed for ANDI, there are advocates for his patenting, or any of several other transgenic
primates which may be constructed in the near future. Of course those in favor of the patent will
bring up OncoMouse™ as a precedent and ask why a mouse can be patented, but a monkey
cannot. Most people are against patenting primates because these primates are close cousins of
humans. Due to the fact that these monkeys have such human qualities gives a positive and negative argument for patenting. The negative aspect of a patent would be the fact that the possibility of patenting humans would be closer to happening. Also, animal rights activists will bring up the point that if humans aren’t allowed to be genetically altered then why can a being that closely shares human qualities be allowed to be altered. The positive aspect to patenting a monkey is the potential to discover cures for human diseases, since primate disease models most closely reflect human physiology.
Another problem with patenting animals is the rush to get patents on animals, since the
OncoMouse™ case. More than 300 patent applications were filed for transgenic animals since
OncoMouse™ went public. Only 9 of these applications have been granted so far (3 in the
European Patent Office, and 6 in the U.S. Patent Office; 5 transgenic mice, 1 transgenic rabbit, and 3 covering all non-human transgenics). Since OncoMouse™ was patented there has been a rush to create new and useful transgenic animals. Unfortunately this type of research cannot be
done without sufficient funding.
64
Animal Rights Groups Against Patenting Animals
CELA Canadian Environmental Law Association
This association was established in 1970 for public interest. It uses existing laws to protect the environment and to advocate environmental law reforms (Canadian Environmental
Las Association, 2003). It is also a free legal advisory clinic for the public, and will act at hearings and in court on behalf of citizens or citizen’s groups who are otherwise unable to afford legal assistance.
BUAV British Union for the Abolition of Vivisection
This association was founded in 1898 for the protection of animal welfare. Vivisection literally means the 'cutting up' of living animals, but has now become more generally used as the term for all experiments on living animals (in vivo) as many animal experiments, such as toxicity tests, will not involve surgical procedures. Their goal as a group is to have all animal testing and research abolished (British Union for the Abolition of Vivisection, 2002).
PETA People for the Ethical Treatment of Animals
This group believes that human beings are just another type of animal, no more important than any smaller or larger creature. They are very serious about their views and dislike anyone who is negatively involved with animals. One commentator for the group stated that, “animal trainers, hunters, fishermen, cattlemen, grocers, and indeed all non-vegetarians are the moral equivalent of cannibals, slave-owners, and death-camp guards” (People for Ethical Treatment of
65 Animals, 2004). They are extremely radical and over the top with protests. They seek total animal liberation and push the limits in regards to taking extreme measures to get their point across and try to create new radical protest activities. “PETA believes that animals deserve the most basic rights—consideration of their own best interests regardless of whether they are useful to humans. Like you, they are capable of suffering and have interests in leading their own lives; therefore, they are not ours to use—for food, clothing, entertainment, or experimentation, or for any other reason.” (People for Ethical Treatment of Animals, 2004)
API Animal Protection Institution
This nonprofit institution was founded in 1968. Their mission is to advocate for the protection of animals from cruelty and exploitation (Animal Protection Institute, 2004).
This group is a violent, underground group of fanatics who plant firebombs in restaurants, destroy butcher shops, and torch research labs (Animal Liberation Front, 2004).
IQP Team Opinion
Following the research performed for this project, the authors of this IQP report believe that patenting animals is justified, as long as it complies with the standard ethics of avoiding cruelty to animals and only partaking in the process to benefit science and medicine.
66
CHAPTER 5: CONCLUSIONS
Throughout this IQP, many of the main issues concerning transgenic animals were
discussed. Transgenic animals are animals that are genetically altered by inserting a transgene to
express a new trait. These animals are created using a variety of techniques, and as research
continues and as these techniques are perfected, new animals (and possibly even humans) may
eventually become part of transgenic studies.
The five major categories of transgenic animals have many applications. In the case of
disease models, scientists can study painful and fatal human diseases with animals that are easily
acquired and maintained. Alzheimer’s Mouse is an example that is very promising because the
animal undergoes no detectable suffering, and it was necessary for further advancement in the
neurodegenerative field. This animal allows society to have a positive outlook on transgenic animals because not only was this mouse crucial to our understanding of what initiates this
disease, but was required to prepare the human clinical trials phase II vaccine. There are still many ethical concerns that need to be considered with disease models such as OncoMouse™, which falls into an ethical grey area because it shows strong medical benefits, but can suffer. The use of genetically engineered animals to simulate human diseases has produced a number of cases in which the animal developed symptoms and diseases that were not the same as the disease it was produced for. One example was with cystic fibrosis mice where their lungs did not become infected (Transgenic Animals, 2000). Therefore it is important that these animals have a strong purpose, are carefully researched and cared for, suffering is minimized, and laws are created to oversee the production of these animals.
67 Transpharmers are a category of transgenic animals that are less controversial than
disease models because the animals do not suffer (they apparently are not aware they are
manufacturing the drug), and thus they hold fewer ethical consequences. They are useful in the
production of proteins and antibiotics that some humans naturally lack. The Genzyme Goats were genetically altered to secrete anticoagulants in their milk that proved to be beneficial to
patients undergoing surgery. Although these animals are nearly controversy free, the well being
of the animal must still be considered to ensure that the animal does not experience any other
bodily changes or secrete any harmful byproducts.
As the demand for organs continues to increase, xenotransplanters provide a positive
outlook for those patients awaiting an organ. These transgenic animals provide great potential
benefits to humans by deceasing rejection by making animal organs more compatible with the
human body. Animals in this category are treated with the utmost respect and they receive much
attention and care. However there are still concerns of the transfer of diseases from animals to
humans. Laws and guidelines must be issued along with continued research on animal diseases
before proceeding with animal to human transplants.
In the opinion of some researchers, genetically altering animals in order to produce leaner
meat goes against the general consensus that humans should eat less meat (Transgenic Animals,
2000). In the case of Superpig, the growth hormone was not targeted to any specific region of
the body so the animal suffered immensely, which was an unforeseen result. As a result, they
terminated the experiment immediately. It is conceivable to think that farmers can keep less
livestock because they get more meat per animal. Also, these transgenic animals could help less
fortunate people and impoverished countries by allowing cheaper, healthier food. However as a
society we have shown to be greedy and would probably create and kill as many animals as we
68 do now, regardless of the fact each animal would produce more meat. Growth hormone overproduction produced no measurable harmful side effects in Superfish, while creating large sizes, so this group supports such experiments in fish, but not in mammals.
In the case of biological models, they further enhance general scientific knowledge while avoiding animal suffering. The transgenic “smart mouse”, Doogie, was altered to over express the NR2B subunit of the NMDA receptor, which caused an enhancement in learning and memory, which could allow scientists to increase these qualities in humans. So long as animal suffering is minimized, and the experiments carefully designed to deepen our scientific understanding, this group supports such experiments.
Transgenic animals will probably always remain controversial, but in most cases provide much benefit and improve human life. It is the overall conclusion of this IQP that transgenic animals need to be considered on a case by case basis, and their overall purpose must be carefully examined before proceeding with the experiment. Many of these animals are necessary for finding a cure for human diseases. It is not acceptable however for animals to suffer without reason because the purpose of the experiment was not clearly thought out. In our opinion, many of the categories of transgenic animals provide a positive outlook for the future and should be accepted by society as a way to improve human life for those who have suffered and those that continue to suffer.
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BIBLIOGRAPHY
Adams, Dave. Cellular Biology Notes. BB 2250. A03. (2003) August 28, 2003; October 6, 2003; October 13, 2003.
Adams, Dave. Personal Communication. (2004).
Alzheimer’s Association. (2004). Accessed May 20, 2004. “What is Alzheimer’s Disease?”
Animal Liberation Front. (2004). Accessed June 15, 2004.
Animal Protection Institute. (2004). Accessed June 15, 2004.
Baguisi, Alexander, et al. (1999) “Production of goats by somatic cell nuclear transfer.” Nature Biology May 1999 Vol. 17: 456-461.
Barre-Sinoussi et al. (1983) Isolation of a Human Retrovirus Associated with Acquired Immune Deficiency Syndrome. Science 220: 868.
“Baylor scientists to construct mouse model for AIDS.” (2001). Baylor College of Medicine. September 19, 2001.
Begley, Sharon. (2001) “Brave New Monkey”. Newsweek, January 22 2001. issue, pp. 50-52 [Andi the transgenic monkey].
Bliss, TV. (1999). Young Receptors Make Smart Mice. Nature 401: 25-27. [Doogie the smartmouse].
Brinster R. L. (1990). “A method for in vitro cultivation of mouse ova from two-cell to blastocyst.” Exp. Cell Res. 32: 205-8, 1963. Accessed June 25, 2004.
Brinster, Ralph and Richard Palmiter. (2001). “Transgenic Mice: Expression of Foreign Genes in Animals”. Accessed June 30, 2004.
British Union for the Abolition of Vivisection. (2000). Transgenic Animals. August 2000. Accessed June 20, 2004.
British Union for the Abolition of Vivisection. (2002). Accessed June 15, 2004.
70
Browder, Leon W. (2001). “The Virtual Embryo”. 12 July 2001. Accessed June 18, 2004.
Bunce, Nigel and Hunt, Jim. (1998-2004). College of Physical Science University of Guelph. The Science Corner: “The AIDS Mouse”. Accessed May 20, 2004.
Butler, D. (2002). Xenotransplant Experts Express Caution Over Knockout Piglets. Nature 415: 103-104.
Buy, Marie. (1997). “Transgenic Animals”. Accessed June 28, 2004.
Cameron, Donald M. (1997). Jurisdiction. “Software Related Patents: Canada.” Accessed June 15, 2004.
Canadian Environmental Law Association. (2002). “Backgrounder: The Harvard Oncomouse Case.” Accessed June 15, 2004.
Canadian Environmental Law Association. (2003). Accessed June 15, 2004.
Chan AW, Chong KY, Martinovich C, Simerly C, and Schaten G. (2001). Transgenic Monkeys Produced by Retroviral Gene Transfer into Mature Oocytes. Science 291: 309-312.
Check, Erika. (2002). Canada Stops Harvard’s Oncomouse in its Tracks. Nature 420: 593.
Devlin, Robert H., Carlo A. Biagi, Timothy Y. Yesaki, Duane E. Smailus, John C. Byatt. Growth of domesticated transgenic fish. Nature 409: 781-782. 15 February 2001.
Einsiedel, Edna F. (2000). “Cloning and its discontents- a Canadian perspective”. Nature Biotechnology. Vol.18: September 2000.
Environment News Service. (2000). Franken Foods: Promise or Peril?. 23 February 2000. Accessed 25 May 2004.
Ezzel, C. (1991) “Milk Engineered ‘Pharm Animals’”. Science News September 7, 1991 Vol. 140 Issue 10 pg 148.
Farlex, Inc. (2004). “Homozygous”.
Feany MB and Bender WW.(2000). A Drosophila Model of Parkinson’s Disease. Nature 404: 394-398.
71 Games, Dora, David Adams, et al. (1995). Alzheimer-Type Neuropathology in Transgenic Mice Overexpressing V717F Beta-Amyloid Precursor Protein. Nature 373: 523-527.
“GM Pharmaceuticals.” (2001). How do we make GM animals? University of Otago.
Gardner, John W. (1965). “Transgenic Animals.” Accessed June 15, 2004.
Goldsmith, Sarah. (1999). “World’s First Cloned Transgenic Goats Born.” Science Daily. 12 May 1999.
Gordon, Jon. M.D., Ph.D. (1997). “Viewpoint: Transgenic Animals as ‘Alternatives’ to Animal Use”. Accessed June 25, 2004.
Han, Hyo-Kyung, Gordon L. Amidon.(2000). Targeted Prodrug Design to Optimize Drig Delivery. AAPS Pharmsci, 2000. Accessed 18 June 2004.
Harmon, Justin. (1999).“Scientists Create Smart Mouse”. September 1, 1999. Accessed May 24, 2004.
Hew, Choy. (2000). Stories Behind Discover. “Serendipity & Perseverance: The Career of a Marine Biologist”. September 2000.
Islam Online (2003). “Fatwa Bank”. Accessed 3 July 2004.
Jackson, George R. (2004). Collaborative Centers for Parkinson’s Disease and Environmental Research. “George R. Jackson”. February 6, 2004. Accessed June 10, 2004.
James, Lachlan S. (2001). Legal definition of "non-obvious". 23 May 2001. Accessed August 4, 2004.
Kaiser, J. (2002). Cloned Pigs May Help Overcome Rejection. Science 295: 25-27. [Xenotransplanters]. http://216.239.39.104/search?q=cache:kALhjt61lBcJ:usitweb.shef.ac.uk/~zzc01ss/mable/mable2 001/j_jackson/Xenotransplantation%2520Literature%2520Review.doc+Kaiser,+J+Cloned+Pigs +May+Help+Overcome+Rejection&hl=en
Kimball, John W. (2004). “Kimball’s Biology Page”. 17 March 2004. Accessed June 5, 2004.
72 Kimball, John W. (2004). “Stem Cells”. 17 March 2004. Accessed June 5, 2004.
Kohn, C. (2001). “First HIV Rat Seen as Best Model for Human Studies”. Science Daily. August 2, 2001. pg 5.
Kopel, David B. Independence Institute Book Review: Animal Rights. (1998). Accessed 3 July 2004.
Leder, Philip. (2003). “Cancer: The Role of Genetic Collaboration”. © 2004 Howard Hughes Medical Institute. Photo: Terri Broderick. Updated August 1, 2003. Accessed May 20, 2004.
Leder P and Stewart T (1984) "Transgenic Non-Human Mammals, The Harvard Oncomouse. US Patent and Trademark Office. Patent #4,736,866. Cambridge, MA.
Leder P and Stewart T (1992) Method for Providing a Cell Culture From a Trangenic Non- Human Mammal. US Patent and Trademark Offfice, Patent #5,087,571.
Leder P and Stewart T (1999) Testing Method Using Transgenic Mice Expressing an Oncogene. US Patent and Trademark Office, Patent #5,925,803.
Lee, Minhyung, Jae Joon Koh, Sang-oh Han, Kyung Soo Ko, Sung Wan Kim. (2002). Prevention of Autoimmune Insulitis by Delivery of Interleukin-4 Plasmid Using a Soluble and Biodegradable Polymeric Carrier. Pharmaceutical Research, Volume 19, Issue 3, March 2002, Pages 246 – 249
Lemonick, M. et al. (2001). “Monkey Business” Science. Vol. 157 Issue 3, pg 50. January 22, 2001.
Lexico Publishing Group, LLC (2004). "Transgene”. Accessed 10 July 2004.
LifeTIMES Magazine. (1997). Issue 1. “Xenotransplantation”.
Logan, J., Sharma, A. (1999). “Potential Use of Genetically Modified Pigs as Organ Donors for Transplantations into Humans”. Clinical & Experimental Pharmacology & Physiology December 1999 Vol. 26 Issue 12 pg 1020
Loma Linda University. (1997). Seventh-day Adventist Guidelines on Genetic Engineering. 22 January 1997. Accessed 3 July 2004.
73 Macer, Daryl R. J. (1990). Shaping Genes. “Ethics, Law and Science of Using New Genetic Technology in Medicine and Agriculture”. Accessed June 15, 2004.
Macer, Darryl and Mary Ann Chen Ng. (2000). “Cloning attitudes to biotechnology in Japan.” Nature Biotechnology. Vol.18: September 2000.
Maher, Brendan A. (2002). The Scientist. “Test Tubes With Tails”. 16 (3): 22. 4 February 2002. Accessed June 12, 2004.
Matheson, John. (2004). Office of Surveillance and Compliance. Center for Veterinary Medicine. “Information for Consumers, FDA: Questions and Answers about Trangenic Fish”.
Medical Information Organization. “Parkinsons”. (2004). Accessed May 24, 2004.
Mitchell, Anne and Somerville, Janet. (2002). Life: Patent Pending. “The Mouse That Made the Lawyers Roar.” Accessed June 15, 2004.
Mooney, David J. and Antonios G. Mikos. (1999). “Growing New Organs.” Scientific American. April 1999.
Neufeldt, Victoria, ed. (1995). “Hunt”. Webster’s New World Compact Dictionary, Third College Edition. NY: Macmillan.
Noonan, Denise. (2003). Monash University. Animal Ethics: Guidelines & Policies. Monitoring Guidelines for Transgenic (Genetically Modified) Animals. 15 October 2003. Accessed 18 July 2004.
O’Brien, Tim. (1998). Compassion in World Farming Trust. Second Edition. “Farm Animal Genetic Engineering”. December 1998. Accessed May 24, 2004.
O’Neil, Dennis (2003) Mendel’s Genetics. 11 August 2003. Accessed 3 July 2004.
People for the Ethical Treatment of Animals. (2004). Accessed June 15, 2004.
PDR Health. “Lactoferrin”. (2004). Accessed May 24, 2004.
74 Pearson, Helen. (2001). “Xenotransplanters welcome rejection: Pig organ transplants teach bone marrow lessons”. July 30 2001.
Phadke M, Billimoria FR, Ninjoor V. (1998). Non enzymatic glycosylation of alpha-1-proteinase inhibitor of human plasma. J Postgrad Med [serial online] 1998 [cited 2004 Jun 11 ];44:29-34
Pharms of the Future: Improving on Mother Nature. “Pharms of the future will yield harvest of edible vaccines for tooth decay”. Accessed May 20, 2004.
PPL Therapeutics. (2004). Homepage. Accessed May 24, 2004.
Pursel, VG et al. (1997) “Transfer of an Ovine Metallothionein-Ovine Growth Hormone Fusion Gene into Swine.” Journal of Animal Science 1997. Vol. 75: 2208-2214.
Reid, W. et al. (2001). “An HIV-1 Transgenic Rat that Develops HIV-related Pathology and Immunology Dysfunction.” PNAS July 31, 2001. Vol. 98 No. 16 pg 9271-9276 http://www.pnas.org/cgi/content/full/98/16/9271?maxtoshow=&HITS=10&hits=10&RESULTF ORMAT=&fulltext=An+HIV- 1+Transgenic+Rat&searchid=1086894319679_6125&stored_search=&FIRSTINDEX=0
Rülicke, Thomas. (2004). Humana Press. Pronuclear Microinjection of Mouse Zygotes. Germ Cell Protocols Volume 2: Molecular Embryo Analysis, Live Imaging, Transgenesis, and Cloning 165- 194 March 2004. Accessed July 13, 2004.
Schaefer, Ricahard A. (1995). LLUMC Legacy: Daring to Care Chapater II: “Baby Fae”.
Schenk D, Barbour R, Dunn W, Gordon G, Grajeda H, Guido T, et al. (1999). Immunization with Amyloid-Beta Attenuates Alzheimer-Disease-Like Pathology in the PDAPP Mouse. Nature 400: 173-177. [Use of the WPI transgenic Alzheimer’s mouse to create world’s first Alzheimer’s vaccine by Elan Parmaceuticals].
Sharples A. and Curley D. (2004). “Harvard Oncomouse – The EPO’s latest word.”
75 Society, Religion and Technology Project. (2001). Church of Scotland: Looking at the ethics of technology for a New Millennium. “Genetically Modified Animals”. 4 May 2001. Accessed 5 July 2004.
Stanford School of Medicine. (2004). Pathology: Transgenic Research Center. “DNA Microinjection”. Accessed 6 July 2004.
Strategis. (2004). “Genetically Engineered Mice”. 26 March 2004. Accessed 18 June 2004.
Tang YP, et al. (1999). Genetic Enhancement of Learning and Memory in Mice. Nature 401: 63-69.
Tayyaba Hasan, Ph.D. (2000). Photodynamic Therapy for Cancer. Accessed 10 July 2004.
The Fisher Center for Alzeheimer’s Disease Foundation (2004) “Why is it important to fund research about Alzheimers Disease?” (2002-2004). Accessed 3 July 2004.
Thompson, Justin. (2002). “The Harvard Mouse (a.k.a. Oncomouse)”. CBC News Online. December 5, 2002. Accessed July 16, 2004.
Touchette, Nancy. (2003). Genome News Network. “Human Embryonic Stem Cells: Where Are They?” 2003 October 30. Accessed June 15, 2004.
“Transgenic Animals.” (2000). 2000 August. Accessed July 21, 2004.
“Transgenic Animals”. (2003). 19 August 2003. Accessed June 28, 2004.
Vogel, Gretchen. (2001). Infant Monkey Carries Jellyfish Gene. Science 291: 226. [Andi the transgenic monkey]. 12 January 2001.
Webnox Corp. (2000-2003). Hyperdictionary. “Retrovirus”. 2000-2003. Accessed 10 July, 2004.
White, Victoria. (1999). “University of Florida Researchers Test Drug from ‘Transgenic Sheep’ in Study at Shands at UF Teaching Hospital”. August 30, 1999.
Wikipedia (2004). Free-Definition. “Retrovirus”. 6 July 2004. Accessed 10 July 2004.
76
Wortman, Marc. (2000). Yale Alumni Magazine: “The Magical Medical Mouse”. March 2000. Accessed June 15, 2004.
Xu, Guang and Howard L. McLeod. (2001). Clinical Cancer Research. Vol. 7, 3314-3324, November 2001. Accessed 10 July 2004.
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